Physics
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New submissions for Fri, 22 Jun 18
 [1] arXiv:1806.07886 [pdf, other]

Title: Evaluation of noise limits of a precision ADC for direct digital signal integration of magnetic measurementsSubjects: Instrumentation and Detectors (physics.insdet); Nuclear Experiment (nuclex)
The characterization of laboratory plasma instabilities, magnetic reconnection and turbulence associated phenomena, require the simultaneous signal sampling from arrays of magnetic sensors (hundreds or even thousands) to obtain spatial resolution, with several hundred kHz for time resolution. Magnetic measurements based on pickup (Mirnov) coil are quite common in experimental pulsed devices for plasma research, thanks to their simplicity and reliability. Being the signal from this type of sensor proportional to the time variation of the magnetic field ($dB/dt$), it has to be timeintegrated to recover the instant value of magnetic field. Depending on the required integration time usually either analog integrators or chopped integrators are used. However these solutions tend to limit the frequency bandwidth in the kHz range, they are not easy to design and build, and require additional fast channels to directly acquire the $dB/dt$ signal to recover the plasma dynamic features at higher frequencies. In this paper we evaluate the feasibility of using a direct single channel precision ADC to allow the simultaneous acquisition of $dB/dt$ measurements and to provide the integrated B measurement by means of digital integration on the new RFXmod2 device. On this purpose we interfaced an existing ADCmodule to a Xilinx Zynq FPGA, in order to evaluate the intrinsic noise and to investigate the feasible integration window of this configuration. The result opens the door to a compact, costeffective and reliable acquisition system, usable for simultaneous realtime control and transient signal recording, scalable from tenths to thousands channels, applicable to a broad class of pulsed plasma experimental devices.
 [2] arXiv:1806.07911 [pdf, other]

Title: Selforganization and Nonuniversal Anomalous Scaling in NonNewtonian TurbulenceComments: 5 pages, 4 figuresSubjects: Fluid Dynamics (physics.fludyn)
We investigate through Direct Numerical Simulations (DNS) the statistical properties of turbulent flows in the inertial subrange for nonNewtonian powerlaw fluids. The structural invariance found for the vortex size distribution is achieved through a selforganized mechanism at the microscopic scale of the turbulent motion that adjusts, according to the rheological properties of the fluid, the ratio between the viscous dissipations inside and outside the vortices. Moreover, the deviations from the K41 theory of the structure functions' exponents reveal that the anomalous scaling exhibits a systematic nonuniversal behavior with respect to the rheological properties of the fluids.
 [3] arXiv:1806.07920 [pdf, other]

Title: Tunable Rydberg excitons maserComments: 4 pages, 5 figuresSubjects: Applied Physics (physics.appph); Mesoscale and Nanoscale Physics (condmat.meshall)
We propose a solid state maser based on Cu2O, where ensemble of highly excited Rydberg exciton states serves as a gain medium. We show that the system is highly tunable with external electric field, allowing for a wide range of emission frequencies. Numerical simulations of system dynamics are performed to optimize the conditions for efficient masing and estimate the emission power.
 [4] arXiv:1806.07940 [pdf]

Title: Improved Magnetron Stability And Reduced Noise In Efficient Transmitters For Superconducting AcceleratorsComments: 3 ppSubjects: Accelerator Physics (physics.accph)
State of the art highcurrent superconducting accelerators require efficient RF sources with a fast dynamic phase and power control. This allows for compensation of the phase and amplitude deviations of the accelerating voltage in the Superconducting RF (SRF) cavities caused by microphonics, etc. Efficient magnetron transmitters with fast phase and power control are attractive RF sources for this application. They are more cost effective than traditional RF sources such as klystrons, IOTs and solidstate amplifiers used with large scale accelerator projects. However, unlike traditional RF sources, controlled magnetrons operate as forced oscillators. Study of the impact of the controlling signal on magnetron stability, noise and efficiency is therefore important. This paper discusses experiments with 2.45 GHz, 1 kW tubes and verifies our analytical model which is based on the charge drift approximation.
 [5] arXiv:1806.07965 [pdf, ps, other]

Title: Nonparaxial electromagnetic Bragg scattering in periodic media with PT symmetrySubjects: Optics (physics.optics)
The evolution of a pair of resonant Bragg modes through a medium characterized by a complex onedimensional $\mathcal{PT}$symmetric periodic permittivity is thoroughly investigated. Analytic solutions of Maxwell's equations are derived beyond the paraxial approximation to investigate the periodic energy exchange that occurs between the Bragg modes for the Hermitian lattices as well as for complex lattices. Three regimes defined by the symmetry breaking point are discussed: below it, above it and at it. These regimes are determined by the existence of four real eigenvalues in the symmetric phase, which collide and coalesce into a pair at the breaking point. Above the critical value each member of the pair bifurcates into a pair of complex values. Therefore, the complex lattice reveals a variety of wave dynamics depending on the gain/loss balance. In all regimes of the transition the signature of $\mathcal{PT}$symmetric systems is present, as the evolution is always nonreciprocal and unidirectional.
 [6] arXiv:1806.07972 [pdf]

Title: Proposal and demonstration of lockin pixels for indirect timeofflight measurements based on germaniumonsilicon technologyAuthors: N. Na, S.L. Cheng, H.D. Liu, M.J. Yang, C.Y. Chen, H.W. Chen, Y.T. Chou, C.T. Lin, W.H. Liu, C.F. Liang, C.L. Chen, S.W. Chu, B.J. Chen, Y.F. Lyu, S.L. ChenSubjects: Instrumentation and Detectors (physics.insdet)
We propose the use of germaniumonsilicon technology for indirect timeofflight depth sensing as well as threedimensional imaging applications, and demonstrate a novel pixel featuring a high quantum efficiency and a large frequency bandwidth. Compared to conventional silicon pixels, our germaniumonsilicon pixels simultaneously maintain a high quantum efficiency and a high demodulation contrast deep into GHz frequency regime, which enable consistently superior depth accuracy in both indoor and outdoor scenarios. Device simulation, system performance comparison, and electrical/optical characterization of the fabricated pixels are presented. Our work paves a new path to highperformance timeofflight sensors and imagers, as well as potential adoptions of eyesafe lasers (wavelengths > 1.4 {\mu}m) that fall outside of the operation window of conventional silicon pixels.
 [7] arXiv:1806.07975 [pdf, other]

Title: Relativistic coupling of phase and amplitude noise in optical interferometrySubjects: Instrumentation and Detectors (physics.insdet); Optics (physics.optics)
Extraneous motion of optical elements in an interferometer lead to excess noise. Typically, fluctuations in the effective path length lead to phase noise, while beampointing leads to apparent amplitude noise. For a transmissive optic moving along the optical axis, neither effect should exist. However, relativity of motion suggests that even in this case, small corrections of order $v/c$ ($v$ the velocity of the optic), give rise to phase and amplitude noise on the light. Here we calculate the effect of this relativistic mechanism of noise coupling, and discuss when such an effect would limit the sensitivity of optical interferometers.
 [8] arXiv:1806.07993 [pdf, other]

Title: Asymmetric concentration dependence of segregation fluxes in granular flowsAuthors: Ryan P. Jones, Austin B. Isner, Hongyi Xiao, Julio M. Ottino, Paul B. Umbanhowar, Richard M. LueptowSubjects: Fluid Dynamics (physics.fludyn)
We characterize the local concentration dependence of segregation velocity and segregation flux in both size and density bidisperse gravitydriven freesurface granular flows as a function of the particle size ratio and density ratio, respectively, using discrete element method (DEM) simulations. For a range of particle size ratios and inlet volume flow rates in sizebidisperse flows, the maximum segregation flux occurs at a small particle concentration less than 0.5, which decreases with increasing particle size ratio. The segregation flux increases up to a size ratio of 2.4 but plateaus from there to a size ratio of 3. In density bidisperse flows, the segregation flux is greatest at a heavy particle concentration less than 0.5 which decreases with increasing particle density ratio. The segregation flux increases with increasing density ratio for the extent of density ratios studied, up to 10. We further demonstrate that the simulation results for size driven segregation are in accord with the predictions of the kinetic sieving segregation model of Savage and Lun.
 [9] arXiv:1806.07997 [pdf, other]

Title: FirstPrinciples Threshold Calculation of Photonic Crystal SurfaceEmitting Lasers Using Rigorous Coupled Wave AnalysisComments: 13 pages, 4 figuresSubjects: Optics (physics.optics)
We show that the threshold of a photonic crystal surfaceemitting laser can be calculated from firstprinciples by the method of rigorous coupled wave analysis (RCWA), which has been widely used to simulate the response spectra of passive periodic structures. Here, the scattering matrix (Smatrix) of a surfaceemitting laser structure with added gain is calculated on the complex frequency plane using RCWA, and the lasing threshold is determined by the value of gain for which the pole of the Smatrix reaches the real axis. This approach can be used for surface emitting laser struc tures in general, and is particularly useful for the surface emitting laser systems with complex inplane structures.
 [10] arXiv:1806.07998 [pdf, other]

Title: Evidence of inverse cascades in the cerebral dynamics: Spontaneous symmetry breaking during arterial inflowSubjects: Biological Physics (physics.bioph); Medical Physics (physics.medph); Neurons and Cognition (qbio.NC)
Cerebral fluid dynamics require a reverse energy mechanism to transport water and metabolites from tissue into veins. Recent findings in active flow of bacteria have shown that such a mechanism involving backward energy cascades, socalled inverse cascades may exist only during spontaneously broken mirrorsymmetries. Here, we wanted to investigate whether and, if so when symmetries break during a heart cycle. We used multiple spin echos (MSE)s in magnetic resonance imaging (MRI) which can detect broken spherical symmetries. We found MSEs in brain tissue which appeared during arterial pulsation in a highly synchronized fashion in most parts of the brain. The timing suggests that the reverse energy flow is initiated during the energy injection of the heartbeat and ends with the isovolumetric vessel contraction. This interleaved process may explain how the illusive pulse wave traveling through the brain emerges as well as underlying principles of cerebral autoregulation and neurovascular coupling.
 [11] arXiv:1806.08001 [pdf, other]

Title: Analog control with two Artificial AxonsComments: 8 pages, 11 figuresSubjects: Biological Physics (physics.bioph); Neurons and Cognition (qbio.NC)
The artificial axon is a recently introduced synthetic assembly of supported lipid bilayers and voltage gated ion channels, displaying the basic electrophysiology of nerve cells. Here we demonstrate the use of two artificial axons as control elements to achieve a simple task. Namely, we steer a remote control car towards a light source, using the sensory input dependent firing rate of the axons as the control signal for turning left or right. We present the result in the form of the analysis of a movie of the car approaching the light source. In general terms, with this work we pursue a constructivist approach to exploring the nexus between machine language at the nerve cell level and behavior.
 [12] arXiv:1806.08008 [pdf, other]

Title: Optimized nonlinear terahertz response of graphene in a parallelplate waveguideSubjects: Applied Physics (physics.appph)
Third harmonic generation of terahertz radiation is expected to occur in monolayer graphene due to the nonlinear relationship between the crystal momentum and the current density. In this work, we calculate the terahertz nonlinear response of graphene inside a parallelplate waveguide including pump depletion, selfphase, and crossphase modulation. To overcome the phase mismatching between the pump field and thirdharmonic field at high input fields due to selfphase and crossphase modulation, we design a waveguide with two dielectric layers with different indices of refraction. We find that, by tuning the relative thicknesses of the two layers, we are able to improve phase matching, and thereby increase the power efficiency of the system by more than a factor of two at high powers. With this approach, we find that dispite the loss in this system, for an incident frequency of $2$ THz, we are able to achieve power efficiencies of $75 \%$ for graphene with low Fermi energies of $20$ meV and up to $35\%$ when the Fermi energy is $100$ meV.
 [13] arXiv:1806.08019 [pdf, other]

Title: Laterally confined photonic crystal surface emitting laser based on monolayer tungsten disulfide operating at room temperatureComments: 10 pages, 4 figuresSubjects: Optics (physics.optics)
We report a photonic crystal surface emitting laser using monolayer tungsten disulfide as the gain medium. The cavity design utilizes a heterostructure in the photonic crystal lattice to provide lateral confinement for a high quality factor with a compact active region. Room temperature continuous wave lasing is realized after integrating monolayer tungsten disulfide flakes onto the silicon nitride photonic crystal on quartz substrate. Highly directional, near surface normal emission has also been experimentally demonstrated.
 [14] arXiv:1806.08022 [pdf, other]

Title: A spacetime smooth artificial viscosity method with wavelet noise indicator and shock collision scheme, Part 2: the 2D caseComments: 42 pages, 21 figuresSubjects: Computational Physics (physics.compph); Numerical Analysis (math.NA)
This is the second part to our companion paper [13]. Herein, we generalize to two space dimensions the Cmethod developed in [14,13] for adding localized, spacetime smooth artificial viscosity to nonlinear systems of conservation laws that propagate shock waves, rarefaction waves, and contact discontinuities. For gas dynamics, the Cmethod couples the Euler equations to scalar reactiondiffusion equations, which we call Cequations, whose solutions serve as spacetime smooth artificial viscosity indicators for shocks and contacts.
We develop a highorder numerical algorithm for gas dynamics in 2D which can accurately simulate the RayleighTaylor (RT) instability with KelvinHelmholtz (KH) rollup of the contact discontinuity, as well as shock collision and bounceback. Solutions to our Cequations not only indicate the location of the shocks and contacts, but also track the geometry of the evolving fronts. This allows us to implement both directionally isotropic and anisotropic artificial viscosity schemes, the latter adding diffusion only in directions tangential to the evolving front.
We additionally produce a novel shock collision indicator function, which naturally activates during shock collision, and then smoothly deactivates. Moreover, we implement a highfrequency 2D waveletbased noise detector together with an efficient and localized noise removal algorithm.
To test the methodology, we use a highly simplified WENObased discretization scheme, devoid of any approximate Riemann solvers. We provide numerical results for some classical 2D test problems, including the RT problem, the Noh problem, a circular explosion problem from the Liska and Wendroff [9] review paper, and a shockwall collision problem.  [15] arXiv:1806.08023 [pdf, ps, other]

Title: A spacetime smooth artificial viscosity method with wavelet noise indicator and shock collision scheme, Part 1: the 1D caseComments: 42 pages, 20 figuresSubjects: Computational Physics (physics.compph); Numerical Analysis (math.NA)
In this first part of two papers, we extend the Cmethod developed in [30] for adding localized, spacetime smooth artificial viscosity to nonlinear systems of conservation laws that propagate shock waves, rarefaction waves, and contact discontinuities in one space dimension. For gas dynamics, the Cmethod couples the Euler equations to a scalar reactiondiffusion equation, whose solution C serves as a spacetime smooth artificial viscosity indicator.
The purpose of this paper is the development of a highorder numerical algorithm for shockwall collision and bounceback. Specifically, we generalize the original Cmethod by adding a new collision indicator, which naturally activates during shockwall collision. Additionally, we implement a new highfrequency waveletbased noise detector together with an efficient and localized noise removal algorithm. To test the methodology, we use a highly simplified WENObased discretization scheme, devoid of any approximate Riemann solvers. We show that our scheme improves the order of accuracy of our WENO algorithm, handles extremely strong discontinuities (ranging up to ten orders of magnitude), allows for shock collision and bounce back, and removes high frequency noise. The wellknown "wall heating" phenomenon is also explained. This method is generalized to two space dimensions in the second part of this work [31].  [16] arXiv:1806.08025 [pdf]

Title: An UltrahighSpeed Waveform Digitizer Prototype Based on Gigabit Ethernet for Plasma DiagnosticsComments: 3 pages,6 figures,21st IEEE Real Time ConferenceSubjects: Instrumentation and Detectors (physics.insdet)
An ultrahighspeed waveform digitizer prototype based on gigabit Ethernet has been developed. The prototype is designed to read out signals of detectors to realize the accurate measurement of various physical quantities for plasma diagnostics. The prototype includes an ultrahighspeed analogtodigital converter (ADC) used to realize high speed digitization, a Xilinx Kintex7 fieldprogrammable gate array (FPGA) used for system configuration and digital signal processing, a DDR3 memory bar for data storage, and a gigabit Ethernet transceiver for interfacing with a computer. The sampling rate of the prototype is up to 5Gsps with 10b resolution. The features of the prototype are described in detail.
 [17] arXiv:1806.08042 [pdf]

Title: Science Education in the 21st CenturyAuthors: Sun KwokSubjects: Physics Education (physics.edph)
The traditional university science curriculum was designed to train specialists in specific disciplines. However, in universities all over the world, science students are going into increasingly diverse careers and the current model does not fit their needs. Advances in technology also make certain modes of learning obsolete. In the last 10 years, the Faculty of Science of the University of Hong Kong has undertaken major curriculum reforms. A sequence of science foundation courses required of all incoming science students are designed to teach science in an integrated manner, and to emphasize the concepts and utilities, not computational techniques, of mathematics. A number of nondiscipline specific common core courses have been developed to broaden students' awareness of the relevance of science to society and the interdisciplinary nature of science. By putting the emphasis on the scientific process rather than the outcome, students are taught how to identify, formulate, and solve diverse problems.
 [18] arXiv:1806.08046 [pdf, other]

Title: Design and Evaluation of LAr Trigger Digitizer Board in the ATLAS PhaseI UpgradeAuthors: Hucheng Chen, Kai Chen, Mauro Citterio, Herve Deschamps, Aude Grabas, Stefano Latorre, Massimo Lazzaroni, Hongbin Liu, Phillippe Schwemling, Stefan Simion, Hao Xu, Heling ZhuComments: This manuscript for conference record of the 21st IEEE Real Time conference onlySubjects: Instrumentation and Detectors (physics.insdet); High Energy Physics  Experiment (hepex)
The LHC upgrade is planned to enhance the instantaneous luminosity during Run 3 from 2021 through 2023. The PhaseI upgrade of the trigger readout electronics for the ATLAS Liquid Argon (LAr) Calorimeters will be installed during the second long shutdown of LHC in 20192020. In this upgrade, the socalled super cells are introduced to provide higher granularity, higher resolution and longitudinal shower shape information from the LAr calorimeters to the level1 trigger processors. A new LAr Trigger Digitizer Board (LTDB) will process and digitize 320 channels of super cell signals, and transmit them via 40 fiber optical links to the back end where data are further processed and transmitted to the trigger processors. Five pairs of bidirectional GBT links are used for slow control from the Frontend LInks eXchange (FELIX) in the ATLAS TDAQ system. LTDB also outputs 64 summed analog signals to the current Tower Builder Board via the new baseplane. A test system is developed to evaluate all functions of the LTDB and carry out the performance measurement. A back end PCIe card is designed which has the circuit to interface to the ATLAS trigger, time and control system. It controls the generation of injection signals to the LTDB for performance test. It also configures and calibrates all ASICs on the LTDB. A frontend test board, test baseplane and a crate are designed to extend the capability of the test setup, which will be used for the production test of the 124 LTDB boards.
 [19] arXiv:1806.08066 [pdf, other]

Title: Dimensionalitydependent crossover in motility of polyvalent burntbridges ratchetsComments: Includes SI, but not supporting moviesSubjects: Biological Physics (physics.bioph); Statistical Mechanics (condmat.statmech); Subcellular Processes (qbio.SC)
The burntbridges ratchet (BBR) mechanism is a model for biased molecular motion whereby the construct destroys track binding sites as it progresses, and therefore acts as a diffusing forager, seeking new substrate sites. Using Monte Carlo simulations that implement the Gillespie algorithm, we investigate the kinetic characteristics of simple polyvalent BBRs as they move on tracks of increasing width. We find that as the track width is increased the BBRs remain nearly ballistic for considerable track widths proportional to the span (leg length) of the polyvalent walker, before transitioning to nearconventional diffusion on twodimensional tracks. We find there exists a tradeoff in BBR track association time and superdiffusivity in the BBR design parameter space of span, polyvalency and track width. Furthermore, we develop an analytical model to describe the ensembleaverage motion on the track and find it is in good agreement with our Gillespie simulation results. This work offers insights into design criteria for de novo BBRs and their associated tracks, where experimentalists seek to optimize directionality and track association time.
 [20] arXiv:1806.08068 [pdf, ps, other]

Title: A simple and efficient numerical procedure to compute the inverse Langevin function with high accuracySubjects: Computational Physics (physics.compph); Soft Condensed Matter (condmat.soft)
The inverse Langevin function is a fundamental part of the statistical chain models used to describe the behavior of polymericlike materials, appearing also in other fields such as magnetism, molecular dynamics and even biomechanics. In the last four years, several approximants of the inverse Lanvegin function have been proposed. In most of them, optimization techniques are used to reduce the relative error of previously published approximants to reach orders of magnitude of order 1E3% to 1E2% In this paper a new simple and efficient numerical approach to calculate the inverse Langevin function is proposed. Its main feature is the drastic reduction of the maximum relative error in all the domain [0,1), halving also the function evaluation times. Specifically, in [0,0.96], the order of magnitude of the maximum relative error is order 1E9%, which corresponds with a maximum absolute error of order 1E14, whereas within [0.91,1) the relative error is of order 1E7%. The method consists in the discretization of the Langevin function, the calculation of the inverse of these discretization points and their interpolation by cubic splines. In order to reproduce the asymptotic behavior of the inverse Langevin function, a [2/1] rational function is considered only in the asymptotic zone and with the same C2 continuity requirements as cubic splines. The use of these C2 piecewise cubic polynomials ensures the continuity of the function up to the second derivative and its integration in any interval.
 [21] arXiv:1806.08070 [pdf]

Title: Data Acquisition System for CSNS Neutron Beam MonitorComments: 21st IEEE Real Time ConferenceSubjects: Instrumentation and Detectors (physics.insdet)
In Chinese Spallation Neutron Source (CSNS), proton beam is used to hit metal tungsten target, and then high flux neutrons are generated for experiments on instruments. For neutron flux spectrum correction, boroncoated GEM, lithium glass and 3He are used as neutron beam monitor in instruments. To be integrated into neutron instrument control, a new DAQ software for neutron beam monitor is developed, called NEROS (Neutron Event Readout System). NEROS is based on EPICS V4 and a unified data format for CSNS neutron beam monitor is defined. The framework and software design of NEROS is introduced in this paper, including realtime data readout, data processing, data visualization and data storage in Nexus format. The performance is evaluated through offline test, Xray test and 252Cf test. The deployment of NEROS and its running result in CSNS instrument commissioning are also introduced in this paper.
 [22] arXiv:1806.08076 [pdf]

Title: The Proton Beam Realtime Monitor System in CSNSComments: 21st IEEE Real Time ConferenceSubjects: Instrumentation and Detectors (physics.insdet)
In Chinese Spallation Neutron Source (CSNS), proton beam is used to hit metal tungsten target, and then high flux neutron are generated for experiments on instruments. For neutron flux spectrum correction, the current of proton beam is for each instrument.
A real time monitor system is developed in CSNS, to monitor, broadcast and record each pulse of proton. Each proton pulse charge is measured and marked with highprecision timestamp. Then, the result of measurement will be broadcasted to control room and each neutron instrument. In control room, the proton charge of each pulse is listened and stored in database by agent program for offline use. The highprecision timestamp can be used to proton charge and neutron data alignment in time scale. The architecture of proton beam monitor system is introduced in this paper. And the performance of this system is evaluated in this paper.  [23] arXiv:1806.08094 [pdf, ps, other]

Title: Highercomponent quadrupole polarizabilities: Estimations for the clock states of the alkaline earthmetal ionsComments: Accepted for publication in Phys. Rev. ASubjects: Atomic Physics (physics.atomph)
Derivations for the higher tensor components of the quadrupole polarizabilities are given and their values for the metastable states of the Ca$^+$, Sr$^+$ and Ba$^+$ alkaline earthmetal ions are estimated. We also give the scalar quadrupole polarizabilities of the ground and metastable states of these ions to compare our results with the previously available theoretical and experimental results. Reasonably good agreement between our calculations with the previous values of scalar quadrupole polarizabilities demonstrate their correctness. The reported scalar and tensor quadrupole polarizabilities could be very useful to estimate the uncertainties due to the gradient of the electric fields in the clock frequencies of the above alkaline earthmetal ions when accuracies of these frequency measurements attain below 10$^{19}$ precision level.
 [24] arXiv:1806.08113 [pdf]

Title: Electrohydrodynamic interaction between droplet pairs in confined shear flowComments: 22 pages, 10 figuresSubjects: Fluid Dynamics (physics.fludyn)
The present study deals with the numerical as well as asymptotic analysis of the electrohydrodynamic interaction between two deformable droplets in a confined shear flow. Considering both the phases as leaky dielectric, we have performed numerical simulations to study the effect of channel confinement on the drop trajectories in the presence of a uniform electric field. Two important varieties of motion are identified in the present analysis, namely (i) the reversing motion and (ii) the passing over motion. The study suggests that conversion of the passing over motion to the reversing motion or vice versa is possible via modulating the strength of the imposed electric field. Such a conversion of the pattern of droplet migration is also possible in a confined domain due to change in different electrical properties of the system. The present numerical model is also able to predict the pattern of the trajectory of individual droplets depending on the initial distance separating the two. For example, a smaller initial distance results in a reversing motion whereas a passing over motion is predicted when the distance between the droplets is significantly large. However, the final positions of the droplets are found to be independent of their initial positions. Interestingly, presence of electric field is found to prevent droplet coalescence to a certain extent depending on its strength, thus rendering the emulsion stable. A small deformation asymptotic model is also developed under the assumption of negligible fluid inertia to support the numerical results for the limiting case of an unbounded flow. The current investigation successfully presents a novel technique to predict the precise positions of a system of droplets in a microchannel and how electric field can be used as a tool to modulate droplet trajectories in an emulsion.
 [25] arXiv:1806.08118 [pdf, other]

Title: Localised response retrieval from Hamamatsu H9500 for a coded aperture neutrongamma imaging system based on an organic pixelated plastic scintillator (EJ29934)Comments: 21st IEEE Real Time Conference, Colonial Williamsburg, USA, June 2018Subjects: Instrumentation and Detectors (physics.insdet)
Localised response of a sensitive light detector, such as Hamamatsu H9500 multi anode photomultiplier tube (MAPMT), is of vital importance for codedaperture imaging systems. When coupled with a suitable sensitive detector (e.g. EJ29934 plastic scintillator), output signals of the MAPMT can be retrieved to infer the interaction location in the pixelated scintillator. Given the number of anodes in H9500 (256), significant processing power would be necessary to handle each pulse individually. Therefore, a readout electronics system was developed, based on resistive network approach, which reduces the number of output signals to individual X and Y coordinates, and subsequently allows particle identification. Coordinates retrieved in this manner can be analysed in real time and used to infer the twodimensional location. Particle type can be also exploited by pulse shape discrimination (PSD) application to the scintillator response. In this study, 169 anodes were used (due to codedaperture design rules), and reduced to two X and Y output signals. These have been digitised using a bespoke FPGA based two channel 14bit 150 MSPS digitiser. The digital data are transferred to a host application using UART to USB converter operating at 12 Mbits/s. Promising results have been observed when the scintillator's response was tested in single particle field of Cs137. However, further tests performed in the mixedfield environment of Cf252 suggest that faster digitiser may be required to obtain the required PSD performance.
 [26] arXiv:1806.08123 [pdf]

Title: Symmetry Breaking of KramersHenneberger Atoms by Ponderomotive ForceAuthors: Qi WeiComments: 7 pagesSubjects: Optics (physics.optics); Atomic Physics (physics.atomph)
It was believed that KramersHenneberger atoms in superintense laser field exhibit structure of "dichotomy". However this is not true for focused laser field. Because in focused laser, KH state electrons experience ponderomotive force, which will break the dichotomous structure.
 [27] arXiv:1806.08157 [pdf, other]

Title: Resistivelylimited current sheet implosions in planar antiparallel (1D) and nullpoint containing (2D) magnetic field geometriesComments: Accepted, will be published Open Access in Physics of Plasmas  refer to main journal for animationsSubjects: Plasma Physics (physics.plasmph); Solar and Stellar Astrophysics (astroph.SR); Fluid Dynamics (physics.fludyn)
Implosive formation of current sheets is a fundamental plasma process. Previous studies focused on the early time evolution, while here our primary aim is to explore the longerterm evolution, which may be critical for determining the efficiency of energy release. To address this problem we investigate two closelyrelated problems, namely: (i) 1D, pinched antiparallel magnetic fields and (ii) 2D, null point containing fields which are locally imbalanced ('nullcollapse' or 'Xpoint collapse'). Within the framework of resistive MHD, we simulate the full nonlinear evolution through three distinct phases: the initial implosion, its eventual halting mechanism, and subsequent evolution posthalting. In a parameter study, we find the scaling with resistivity of current sheet properties at the halting time is in good agreement  in both geometries  with that inferred from a known 1D similarity solution. We find that the halting of the implosions occurs rapidly after reaching the diffusion scale by sudden Ohmic heating of the dense plasma within the current sheet, which provides a pressure gradient sufficient to oppose further collapse and decelerate the converging flow. This backpressure grows to exceed that required for force balance and so the postimplosion evolution is characterised by the consequences of the current sheet `bouncing' outwards. These are: (i) the launching of propagating fast MHD waves (shocks) outwards and (ii) the widthwise expansion of the current sheet itself. The expansion is only observed to stall in the 2D case, where the pressurisation is relieved by outflow in the reconnection jets. In the 2D case, we quantify the maximum amount of current sheet expansion as it scales with resistivity, {and analyse the structure of the reconnection region which forms postexpansion, replete with Petschektype slow shocks and fast termination shocks.
 [28] arXiv:1806.08162 [pdf, other]

Title: The electrical conductivity tensor of $β$Ga$_{2}$O$_{3}$ analyzed by van der Pauw measurements: Inherent anisotropy, offdiagonal element, and the impact of grain boundariesAuthors: Christian Golz, Vanesa Hortelano, Fariba Hatami, W. Ted Masselink, Zbigniew Galazka, Oliver BierwagenSubjects: Applied Physics (physics.appph); Materials Science (condmat.mtrlsci)
The semiconducting oxide $\beta$Gallium Oxide ($\beta$Ga$_{2}$O$_{3}$) possesses a monoclinic unit cell whose low symmetry generally leads to anisotropic physical properties. For example, its electrical conductivity is generally described by a polar symmetrical tensor of second rank consisting of four independent components. Using van der Pauw measurements in a welldefined square geometry on differentlyoriented highquality bulk samples and the comparison to finite element simulations we determine the ratio of all elements of the $\beta$Ga$_{2}$O$_{3}$ 3dimensional electrical conductivity tensor. Despite the structural anisotropy a nearly isotropic conductivity was found with the principal conductivities deviating from each other by less than 5 % and the offdiagonal element being less than 4 % of the diagonal ones. Analysis of the temperature dependence of the anisotropy and mobility of differently doped samples suggest this isotropic behavior to apply for phononscattering as well as ionizedimpurity scattering. We demonstrate that significantly higher anisotropies can be caused by extended structural defects in the form of lowangle grain boundaries for which we determined energy barriers of multiple 10 meV.
 [29] arXiv:1806.08172 [pdf]

Title: Sub20 nm Nanopores Sculptured by a Single Nanosecond Laser PulseAuthors: Yanwen Yuan, Guangyuan Li, Hamed Zaribafzadeh, María de la Mata, Pablo CastroHartmann, Qing Zhang, Jordi Arbiol, Qihua XiongComments: The work of this paper was done in 2013Subjects: Biological Physics (physics.bioph)
Singlemolecule based 3rd generation DNA sequencing technologies have been explored with tremendous effort, among which nanopore sequencing is considered as one of the most promising to achieve the goal of $1,000 genome project towards personalized medicine. Solid state nanopore is consented to be complementary to protein nanopore and subjected to extensive investigations in the past decade. However, the prevailing solidstate nanopore preparation still relies on focused ion or electron beams, which are expensive and time consuming. Here we demonstrate the fabrication of nanopores down to 19 nm with a single nanosecond laser pulse. The laser drilling process is understood based upon a 2D axisymmetric transient heat transfer model, which predicts the laser fluencedependent pore size distribution and shape with excellent agreement to electron microscopy and tomography analysis. Asdrilled nanopore devices (26 nm) exhibit adequate sensitivity to detect single DNA molecule translocations and discriminate unfolded or folded events. Sub10 nm nanopores can be readily achieved upon a thin layer of alumina deposition by atomic layer deposition, which further improves the DNA translocation signal to noise ratio considerably. Our work provides a solution for fast, lowcost and efficient largescale fabrication of solid state nanopore devices for the 3rd generation nanopore sequencing.
 [30] arXiv:1806.08179 [pdf]

Title: Classification of red blood cell shapes in flow using outlier tolerant machine learningComments: 15 pages, published in PLoS Comput Biol, open accessJournalref: PLoS Comput Biol. 2018 Jun 15;14(6):e1006278Subjects: Biological Physics (physics.bioph); Fluid Dynamics (physics.fludyn); Other Quantitative Biology (qbio.OT)
The manual evaluation, classification and counting of biological objects demands for an enormous expenditure of time and subjective human input may be a source of error. Investigating the shape of red blood cells (RBCs) in microcapillary Poiseuille flow, we overcome this drawback by introducing a convolutional neural regression network for an automatic, outlier tolerant shape classification. From our experiments we expect two stable geometries: the socalled `slipper' and `croissant' shapes depending on the prevailing flow conditions and the cellintrinsic parameters. Whereas croissants mostly occur at low shear rates, slippers evolve at higher flow velocities. With our method, we are able to find the transition point between both `phases' of stable shapes which is of high interest to ensuing theoretical studies and numerical simulations. Using statistically based thresholds, from our data, we obtain socalled phase diagrams which are compared to manual evaluations. Prospectively, our concept allows us to perform objective analyses of measurements for a variety of flow conditions and to receive comparable results. Moreover, the proposed procedure enables unbiased studies on the influence of drugs on flow properties of single RBCs and the resulting macroscopic change of the flow behavior of whole blood.
 [31] arXiv:1806.08180 [pdf]

Title: Upgrade of the Data Acquisition and Control System of Microwave Reflectometry on the Experimental Advanced Superconducting TokamakAuthors: Fei Wen, Haoming Xiang, Tao Zhang, Yuming Wang, Xiang Han, Hao Qu, Fubin Zhong, Kaixuan Ye, Mingfu Wu, Gongshun Li, Shoubiao Zhang, Xiang GaoComments: 21st IEEE Real Time ConferenceSubjects: Instrumentation and Detectors (physics.insdet)
The reflectometry on Experimental Advanced Superconducting Tokamak (EAST) is undergoing an upgrade for more comprehensive measurement of plasma density profile and fluctuation. The Data Acquisition and Control System (DACS) has been redeveloped to satisfy the requirements of the upgraded reflectometry. The profile reflectometry works in 30110 GHz (Xmode) and 4090GHz (Omode), when the fluctuation reflectometry operates at 20 fixed frequency points in 50110GHz (Xmode) and 2060GHz (Omode). The PXIebased DACS includes two 8channel 14bit 250MSPS digitizers and ten 8channel 12bit 60MSPS digitizers. A selfdeveloped 5channel 250MSPS arbiter waveform generator (AWG) is used to control voltage control oscillators for frequency sweeping. A trigger and clock manger and a timing module receive the trigger and clock signal from central controller and synchronize all the digitizers and the AWG. The total data rate from digitizers is 2515 MB/S. The Data from digitizers is streamed to a disk array (RAID 0) with data throughput capacity of 3000 MB/S. Meanwhile, selected data is transported to a FPGA based realtime data processing module, which utilize a pretrained neural network to calculate the plasma density profile. Now the new reflectometry is being installed on EAST, and its performance will be tested in experimental campaign after 2018.
 [32] arXiv:1806.08188 [pdf, ps, other]

Title: Enhanced Absorption of Waves in Hyperuniform Disordered MediaSubjects: Optics (physics.optics)
We study the propagation of waves in a set of absorbing subwavelength scatterers positioned on a stealth hyperuniform point pattern. We show that spatial correlations in the disorder substantially enhance absorption compared to a fully disordered structure with the same density of scatterers. The nonresonant nature of the mechanism provides broad angular and spectral robustness. These results open perspectives in the design of lowdensity disordered materials with blackbodylike absorption.
 [33] arXiv:1806.08193 [pdf, other]

Title: Realtime nonintrusive depth estimation of buried radioactive wastes based on approximate threedimensional relative attenuation modelComments: 21st IEEE Real Time Conference, Colonial Williamsburg, USA, June 2018Subjects: Instrumentation and Detectors (physics.insdet)
A new method for nonintrusive estimation of the depth of buried radioactive waste have been developed. The method is based on an approximate threedimensional relative attenuation model that exploits the variation in the intensities of the radiation image obtained on the surface of the material in which the radioactive source is buried. Experimental results using an organic liquid scintillator detector showed that the method is able to estimate the depth of a 329 kBq Cs137 radioactive point source buried up to 12 cm in sand.
 [34] arXiv:1806.08207 [pdf, other]

Title: Fractal dimensions and trajectory crossings in correlated random walksComments: 11 pages, 5 figuresSubjects: Fluid Dynamics (physics.fludyn)
We study spatial clustering in a discrete, onedimensional, stochastic, toy model of heavy particles in turbulence and calculate the spectrum of multifractal dimensions $D_q$ as functions of a dimensionless parameter, $\alpha$, that plays the role of an inertia parameter. Using the fact that it suffices to consider the linearized dynamics of the model at small separations, we find that $D_q =D_2/(q1)$ for $q=2,3,\ldots$. The correlation dimension $D_2$ turns out to be a nonanalytic function of the inertia parameter in this model. We calculate $D_2$ for small $\alpha$ up to the nexttoleading order in the nonanalytic term.
 [35] arXiv:1806.08220 [pdf, ps, other]

Title: A unified theory for both massless, massive vector fields and nontriviality of physical Hilbert space of this theoryAuthors: Susobhan MandalComments: 8 pagesSubjects: General Physics (physics.genph); High Energy Physics  Theory (hepth)
In this article, I talk about a model which is known and often used to unify both massless and massive vector freefield theory, discuss the importance of auxiliary scalar field introduced in the Lagrangian density that we consider in this theory which turns out to be unphysical in massive vector field case which I also show. But for massless theory in 3+1dimensional case, I show that this auxiliary field makes the physical Hilbert space nontrivial in terms of introducing an extra physical degree of freedom or an extra nontrivial kind of polarized state which is absent in Maxwell's electrodynamics theory (freemassless vector field theory). And this state is also shown to be present in 1+1dimensional theory whereas there is no onshell photon in Maxwell's theory of electromagnetism, which is a massless vector field theory.
 [36] arXiv:1806.08221 [pdf, ps, other]

Title: Quaternionic approach to dual Magnetohydrodynamics of dyonic cold plasmaComments: 20 pagesSubjects: General Physics (physics.genph)
The dual magnetohydrodynamics of dyonic plasma describes the study of electrodynamics equations along with the transport equations in the presence of electrons and magnetic monopoles. In this paper, we formulate the quaternionic dual fields equations, namely, the hydroelectric and hydromagnetic fields equations which are an analogous to the generalized Lamb vector field and vorticity field equations of dyonic cold plasma. Further, we derive the quaternionic DiracMaxwell equations for dual magnetohydrodynamics of dyonic cold plasma. We also obtain the quaternionic dual continuity equations that describe the transport of dyonic fluid. Finally, we establish an analogy of Alfven wave equation which may relate one of the flow of magnetic monopoles in the dyonic cold plasma. The present quaternionic formulation for dyonic cold plasma is well invariant under the duality, Lorentz and CPT transformations.
 [37] arXiv:1806.08222 [pdf, other]

Title: Time in quantum mechanics and the local nonconservation of the probability currentAuthors: G. ModaneseComments: 16 pages, 5 figuresSubjects: General Physics (physics.genph)
In relativistic quantum field theory with local interactions, charge is locally conserved. This implies local conservation of probability for the Dirac and KleinGordon wavefunctions, as special cases; and then in turn for nonrelativistic quantum field theory and for the Schroedinger and GinzburgLandau equations, regarded as low energy limits. Quantum mechanics, however, is wider than quantum field theory, as an effective model of reality. For instance, fractional quantum mechanics and Schroedinger equations with nonlocal terms have been successfully employed in several applications. The nonlocality of these formalisms is strictly related to the problem of time in quantum mechanics. We compute explicitly for continuum wave packets the terms of the fractional Schroedinger equation and of the nonlocal Schroedinger equation by Lenzi et al. which break the local current conservation, and discuss their physical significance. The results are especially relevant for the electromagnetic coupling of these wavefunctions. A connection with the nonlocal Gorkov equation for superconductors and their proximity effect is also outlined.
 [38] arXiv:1806.08228 [pdf, other]

Title: ElectroNeutral Models for dynamic PoissonNernstPlanck System: 2D CaseComments: arXiv admin note: text overlap with arXiv:1711.07562Subjects: Biological Physics (physics.bioph)
The PoissonNernstPlanck (PNP) system is a standard model for describing ion transport. In many applications, e.g., ions in biological tissues, the presence of thin boundary layers poses both modelling and computational challenges. In a previous paper, we derived simplified electroneutral (EN) models in one dimensional space where the thin boundary layers are replaced by effective boundary conditions. In this paper, we extend our analysis to the two dimensional case where the EN model enjoys even greater advantages. First of all, it is much cheaper to solve the EN models numerically. Secondly, EN models are easier to deal with compared with the original PNP system, therefore it is also easier to derive macroscopic models for cellular structures using EN models. The multiion case with general boundary is considered, for a variety of boundary conditions including either Dirichlet or flux boundary conditions. Using systematic asymptotic analysis, we derive a variety of effective boundary conditions directly applicable to the EN system for the bulk region. To validate the EN models, numerical computations are carried out for both the EN and original PNP system, including the propagation of action potential for both myelinated and unmyelinated axons. Our results show that solving the EN models is much more efficient than the original PNP system.
 [39] arXiv:1806.08234 [pdf, other]

Title: Neural Networks as Globally Optimal Multilayer Convolution Architectures for Learning Fluid FlowsComments: Article in review. arXiv admin note: text overlap with arXiv:1805.12547 by other authorsSubjects: Computational Physics (physics.compph)
In this work we explore globally optimal multilayer convolution models such as feed forward neuralnetworks (FFNN) for learning and predicting dynamics from transient fluid flow data. While machine learning in general depends on data quality relative to the underlying dynamics of the system, it is important for a given datadriven learning architecture to make the most of this available information. To this end, we cast the suite of recently popular datadriven learning approaches that approximate the Markovian dynamics through a linear model in a higherdimensional feature space as a multilayer architecture similar to neural networks, but with layerwise locally optimal convolution mappings. As a contrast, we also represent the traditional neural networks with some slight modifications as a multilayer architecture, but with convolution maps optimized in response to the global learning cost (i.e. not the cost of learning across two immediate layers). We show through examples of datadriven learning of canonical fluid flows that globally optimal FFNNlike methods owe their success to leveraging the extended learning parameter space available in multilayer models to achieve a common goal of minimizing the training cost function while incorporating nonlinear function maps between layers. On the other hand, locally optimal multilayer models also show improvement from the same factors, but behave like shallow neural networks requiring much larger hidden layers to achieve comparable learning and prediction accuracy. We illustrate these ideas by learning the dynamics from snapshots of training data and predicting the temporal evolution of canonical nonlinear fluid flows.
 [40] arXiv:1806.08259 [pdf, other]

Title: Dynamic Network 3  0 FIFA Rankings: Replacing an inaccurate, biased, and exploitable football ranking systemAuthors: Sam AbernethySubjects: Physics and Society (physics.socph); Social and Information Networks (cs.SI)
International football results are interpreted as a directed network to give each team a rank. Two networkbased models  Static and Dynamic  are constructed and compared with the current FIFA Rankings. The Dynamic Model outperforms the FIFA Rankings in terms of World Cup predictive accuracy, while also removing continental bias and reducing the vulnerability of the FIFA Rankings to exploitation. This is done using two intuitive parameters  relative importance of indirect wins and bygone wins  whose values are determined to be 0.07 and 0.9 respectively. We suggest that FIFA should implement this model as its future ranking system.
 [41] arXiv:1806.08265 [pdf, other]

Title: Development and Characterization of 6gap Bakelite Multigap Resistive Plate ChamberSubjects: Instrumentation and Detectors (physics.insdet)
The Multigap Resistive Plate Chamber (MRPC) is an advanced form of Resistive Plate Chamber (RPC) detector where the gas gap is divided into subgaps. MRPCs are known for their good time resolution and detection efficiency for charged particles. They have found suitable applications in several high energy physics experiments like ALICE in LHC, CERN, Geneva, Switzerland, and STAR in RHIC, BNL, USA. As they have very good time resolution and are of low cost, they can be a suitable replacement for very expensive scintillators used in Positron Emission Tomography Imaging. The MRPCs that are being used nowadays are developed with glass electrodes. We have made an attempt to develop a 6gap MRPC using bakelite electrodes. The outer electrodes are of dimensions 15 cm $\times$ 15 cm $\times$ 0.3 cm and the inner electrodes are of dimension 14 cm $\times$ 14 cm $\times$ 0.05 cm. The glossy finished electrode surfaces have not been treated with any oil like linseed, silicone for smoothness. The performance of the detector has been studied measuring the efficiency, noise rate and time resolution with cosmic rays. This effort is towards the development of a prototype for Positron Emission Tomography with the TimeOfFlight technique using MRPCs. Details of the development procedure and performance studies have been presented here.
 [42] arXiv:1806.08280 [pdf]

Title: Fourier plane optical microscopy and spectroscopyComments: Submitted to Wiley VCH encyclopedia of applied physicsSubjects: Optics (physics.optics); Mesoscale and Nanoscale Physics (condmat.meshall); Applied Physics (physics.appph)
Intensity, wavevector, phase, and polarization are the most important parameters of any light beam. Understanding the wavevector distribution has emerged as a very important problem in recent days, especially at nanoscale. It provides unique information about the lightmatter interaction. Back focal plane or Fourier plane imaging and spectroscopy techniques help to measure wavevector distribution not only from single molecules and single nanostructures but also from metasurfaces and metamaterials. This review provides a birdseye view on the technique of back focal imaging and spectroscopy, different methodologies used in developing the technique and applications including angular emission patterns of fluorescence and Raman signals from molecules, elastic scattering etc. We first discuss on the information one can obtain at the back focal plane of the objective lens according to both imaging and spectroscopy viewpoints and then discuss the possible configurations utilized to project back focal plane of the objective lens onto the imaging camera or to the spectroscope. We also discuss the possible sources of error in such measurements and possible ways to overcome it and then elucidate the possible applications.
 [43] arXiv:1806.08285 [pdf, other]

Title: Photons in the presence of parabolic mirrorsComments: 23 pages, 5 figuresSubjects: Optics (physics.optics); Quantum Physics (quantph)
We present a vectorial analysis of the behavior of the electromagnetic field in the presence of boundaries with parabolic geometry. The relevance of the use of symmetries to find explicit closed expressions for the electromagnetic fields is emphasized. Polarization and phase related angular momenta of light have an essential role in the proper definition of the generator $\mathfrak{A}_3$ of a symmetry transformation that distinguishes the parabolic geometry. Quantization of the electromagnetic field in terms of the resulting elementary modes is performed. The important case of a boundary defined by an ideal parabolic mirror is explicitly worked out. The presence of the mirror restricts the eigenvalues of $\mathfrak{A}_3$ available to the electric and magnetic fields of a given mode via compact expressions. Modes previously reported in the literature are particular cases of those described in this work.
 [44] arXiv:1806.08289 [pdf, ps, other]

Title: Magnoninduced highorder sideband generationComments: 5 pages, 4 figuresSubjects: Optics (physics.optics)
Magnon Kerr nonlinearity plays crucial roles in the study of cavity optomagnonics system and may bring many novel physical phenomena and important applications. In this work, we report the investigation of high order sideband generation induced by magnon Kerr nonlinearity in a cavitymagnon system, which is critically lacking in this emerging research field. We uncover that the driving field plays a significant role in controlling the generation and amplification of the higherorder sidebands and the sideband spacing can be adjusted by regulating the beat frequency between the pump laser and the probe laser, which is extremely eventful for the spacing modulation of the sideband spectrum. Based on the recent experimental progress, our results deepen our cognition into optomagnonics nonlinearity and may find interesting applications in optical frequency metrology and optical communications.
 [45] arXiv:1806.08293 [pdf, other]

Title: Beam tests of silicon pixel 3Dsensors developed at SINTEFAuthors: Ole Dorholt, Tor Erik Hansen, Andreas Heggelund, Angela Kok, Nicola Pacifico, Ole Rohne, Heidi Sandaker, Bjarne Stugu, Zongchang Yang, Marco Bomben, Andre Rummler, Jens WeingartenSubjects: Instrumentation and Detectors (physics.insdet)
For the purpose of withstanding very high radiation doses, silicon pixel sensors with a 3D electrode geometry are being developed. Detectors of this kind are highly interesting for harch radiation environments such as expected in the High Luminosity LHC, but also for space physics and medical applications. In this paper, prototype sensors developed at SINTEF are presented and results from tests in a pion beam at CERN are given. These tests shows that these 3D sensors perform as expected with full efficiency at bias voltages between 5 and 15V.
 [46] arXiv:1806.08312 [pdf, other]

Title: The KATRIN Superconducting Magnets: Overview and First Performance ResultsAuthors: M. Arenz, W.J. Baek, M. Beck, A. Beglarian, J. Behrens, T. Bergmann, A. Berlev, U. Besserer, K. Blaum, T. Bode, B. Bornschein, L. Bornschein, T. Brunst, N. Buzinsky, S. Chilingaryan, W. Q. Choi, M. Deffert, P. J. Doe, O. Dragoun, G. Drexlin, S. Dyba, F. Edzards, K. Eitel, E. Ellinger, R. Engel, S. Enomoto, M. Erhard, D. Eversheim, M. Fedkevych, J. A. Formaggio, F. M. Fränkle, G. B. Franklin, F. Friedel, A. Fulst, n W. Gil, F. Glück, A. Gonzalez Ureña, S. Grohmann, R. Grössle, R. Gumbsheimer, M. Hackenjos, V. Hannen, F. Harms, N. Haußmann, F. Heizmann, K. Helbing, W. Herz, S. Hickford, D. Hilk, M. A. Howe, A. Huber, A. Jansen, J. Kellerer, N. Kernert, L. Kippenbrock, M. Kleesiek, M. Klein, A. Kopmann, M. Korzeczek, A. Kovalík, B. Krasch, M. Kraus, L. Kuckert, et al. (61 additional authors not shown)Subjects: Instrumentation and Detectors (physics.insdet)
The KATRIN experiment aims for the determination of the effective electron antineutrino mass from the tritium betadecay with an unprecedented subeV sensitivity. The strong magnetic fields, designed for up to 6~T, adiabatically guide $\beta$electrons from the source to the detector within a magnetic flux of 191~Tcm$^2$. A chain of ten single solenoid magnets and two larger superconducting magnet systems have been designed, constructed, and installed in the 70mlong KATRIN beam line. The beam diameter for the magnetic flux varies from 0.064~m to 9~m, depending on the magnetic flux density along the beam line. Two transport and tritium pumping sections are assembled with chicane beam tubes to avoid direct "lineofsight" molecular beaming effect of gaseous tritium molecules into the next beam sections. The sophisticated beam alignment has been successfully crosschecked by electron sources. In addition, magnet safety systems were developed to protect the complex magnet systems against coil quenches or other system failures. The main functionality of the magnet safety systems has been successfully tested with the two large magnet systems. The complete chain of the magnets was operated for several weeks at 70$\%$ of the design fields for the first test measurements with radioactive krypton gas. The stability of the magnetic fields of the source magnets has been shown to be better than 0.01$\%$ per month at 70$\%$ of the design fields. This paper gives an overview of the KATRIN superconducting magnets and reports on the first performance results of the magnets.
 [47] arXiv:1806.08314 [pdf]

Title: Coherent multidimensional spectroscopy of dilute gasphase nanosystemsAuthors: Lukas Bruder, Ulrich Bangert, Marcel Binz, Daniel Uhl, Romain Vexiau, Nadia BouloufaMaafa, Olivier Dulieu, Frank StienkemeierSubjects: Chemical Physics (physics.chemph)
Twodimensional electronic spectroscopy (2DES) is one of the most powerful spectroscopic techniques, capable of attaining a nearly complete picture of a quantum system including its couplings, quantum coherence properties and its realtime dynamics. While successfully applied to a variety of condensed phase samples, high precision experiments on isolated quantum systems in the gas phase have been so far precluded by insufficient sensitivity. However, such experiments are essential for a precise understanding of fundamental mechanisms and to avoid misinterpretations, e.g. as for the nature of quantum coherences in energy transport. Here, we solve this issue by extending 2DES to isolated nanosystems in the gas phase prepared by helium nanodroplet isolation in a molecular beamtype experiment. This approach uniquely provides high flexibility in synthesizing tailored, quantum stateselected model systems of single and manybody properties. For demonstration, we deduce a precise and conclusive picture of the ultrafast coherent dynamics in isolated highspin Rb2 molecules and present for the first time a dynamics study of the systembath interaction between a single molecule (here Rb3) and a superfluid helium environment. The results demonstrate the unique capacity to elucidate prototypical interactions and dynamics in tailored quantum systems and bridges the gap to experiments in ultracold quantum science.
 [48] arXiv:1806.08318 [pdf, other]

Title: Diffusion vs. direct transport in the precision of morphogen readoutSubjects: Biological Physics (physics.bioph); Cell Behavior (qbio.CB)
Morphogen profiles allow cells to determine their position within a developing organism, but the mechanisms behind the formation of these profiles are still not well agreed upon. Here we derive fundamental limits to the precision of morphogen concentration sensing for two canonical models: the diffusion of morphogen through extracellular space and the direct transport of morphogen from source cell to target cell, e.g. via cytonemes. We find that direct transport establishes a morphogen profile without adding extrinsic noise. Despite this advantage, we find that for sufficiently large values of population size and profile length, the diffusion mechanism is many times more precise due to a higher refresh rate of morphogen molecules. Our predictions are supported by data from a wide variety of morphogens in developing organisms.
 [49] arXiv:1806.08326 [pdf, other]

Title: Changes in the boundarylayer structure at the edge of the ultimate regime in vertical natural convectionJournalref: J. Fluid Mech. 825 (2017) 550572Subjects: Fluid Dynamics (physics.fludyn)
In thermal convection for very large Rayleigh numbers ($Ra$), the thermal and viscous boundary layers (BL) undergo a transition from a classical state to an ultimate state. In the former state, the BL thicknesses follow a laminarlike PrandtlBlasiusPolhausen scaling, whereas in the latter, the BLs are turbulent with logcorrections in the sense of Prandtl and von K\'arm\'an. Here, we report evidence of this transition via changes in the BL structure of vertical natural convection (VC), which is a buoyancy driven flow between differentially heated vertical walls. The dataset spans $Ra$values from $10^5$ to $10^9$ and Prandtl number value of 0.709. For this $Ra$ range, the VC flow exhibits classical state behaviour in a global sense. Yet, with increasing $Ra$, we observe that nearwall highershear patches occupy increasingly larger fractions of the wallareas, which suggest that the BLs are undergoing a transition from the classical state to the ultimate sheardominated state. The presence of streaky structuresreminiscent of the nearwall streaks in canonical wallbounded turbulencefurther supports the notion of this transition. Within the highershear patches, conditionally averaged statistics yield a logvariation in the local mean temperature profiles, in agreement with the loglaw of the wall for mean temperature, and a $Ra^{0.37}$ effective powerlaw scaling of the local Nusselt number, consistent with the logarithmically corrected 1/2power law scaling predicted for ultimate thermal convection for very large $Ra$. Collectively, the results from this study indicate that turbulent and laminarlike BL coexist in VC at moderate to high $Ra$ and this transition from the classical state to the ultimate state manifests as increasingly larger sheardominated patches, consistent with the findings reported for RayleighB\'enard convection and TaylorCouette flows.
 [50] arXiv:1806.08341 [pdf, other]

Title: Bulk scaling in wallbounded and homogeneous vertical natural convectionJournalref: J. Fluid Mech. 841 (2018) 825850Subjects: Fluid Dynamics (physics.fludyn)
Previous numerical studies on homogeneous RayleighB\'enard convection, which is RayleighB\'enard convection (RBC) without walls, and therefore without boundary layers, have revealed a scaling regime that is consistent with theoretical predictions of bulkdominated thermal convection. In this socalled asymptotic regime, previous studies have predicted that the Nusselt number ($Nu$) and the Reynolds number ($Re$) vary with the Rayleigh number ($Ra$) according to $Nu\sim Ra^{1/2}$ and $Re\sim Ra^{1/2}$ at small Prandtl number ($Pr$). In this study, we consider a flow that is similar to RBC but with the direction of temperature gradient perpendicular to gravity instead of parallel; we refer to this configuration as vertical natural convection (VC). Since the direction of the temperature gradient is different in VC, there is no exact relation for the average kinetic dissipation rate, which makes it necessary to explore alternative definitions for $Nu$, $Re$ and $Ra$ and to find physical arguments for closure, rather than making use of the exact relation between $Nu$ and the dissipation rates as in RBC. Once we remove the walls from VC to obtain the homogeneous setup, we find that the aforementioned $1/2$powerlaw scaling is present, similar to the case of homogeneous RBC. When focussing on the bulk, we find that the Nusselt and Reynolds numbers in the bulk of VC too exhibit the $1/2$powerlaw scaling. These results suggest that the $1/2$powerlaw scaling may even be found at lower Rayleigh numbers if the appropriate quantities in the turbulent bulk flow are employed for the definitions of $Ra$, $Re$ and $Nu$. From a stability perspective, at low to moderate$Ra$, we find that the timeevolution of the Nusselt number for homogenous vertical natural convection is unsteady, which is consistent with the nature of the elevator modes reported in previous studies on homogeneous RBC.
Crosslists for Fri, 22 Jun 18
 [51] arXiv:1806.07879 (crosslist from qbio.NC) [pdf, ps, other]

Title: Integrated information in the thermodynamic limitComments: arXiv admin note: substantial text overlap with arXiv:1805.00393Subjects: Neurons and Cognition (qbio.NC); Disordered Systems and Neural Networks (condmat.disnn); Statistical Mechanics (condmat.statmech); Adaptation and SelfOrganizing Systems (nlin.AO); Biological Physics (physics.bioph)
The ability to integrate information into a unified coherent whole is a fundamental capacity of many biological and cognitive systems. Integrated Information Theory (IIT) provides a mathematical approach to quantify the level of integration in a system. Nevertheless, it is not yet well understood how integration scales up with the size of a system or with different temporal scales of activity, nor how a system maintains its integration as its interacts with its environment. We argue that modelling and understanding how measures of information integration operate in these scenarios is fundamental to adequately capture integration in systems such as the brain. We propose a simplified and modified version of integrated information {\phi} in order to explore these questions. Using mean field approximations, we measure {\phi} in a kinetic Ising models of infinite size. We find that information integration diverges in some cases when the system is near critical points in continuous phase transitions. Moreover, we find that we can delimit the boundary of a system with respect to its environment by comparing the divergent integrative tendencies of system and systemenvironment processes respectively. Finally, we model a system that maintains integrated information when interacting with a range of different environments by generating a critical surface spanning a parametric region of the environment. We conclude by discussing how thinking about integrated information in the thermodynamic limit opens fruitful research avenues for studying the organization of biological and cognitive systems.
 [52] arXiv:1806.07903 (crosslist from qbio.NC) [pdf, other]

Title: Finding influential nodes for integration in brain networks using optimal percolation theoryAuthors: Gino Del Ferraro, Andrea Moreno, Byungjoon Min, Flaviano Morone, Úrsula PérezRamírez, Laura PérezCervera, Lucas C. Parra, Andrei Holodny, Santiago Canals, Hernán A. MakseComments: 20 pages, 6 figures, Supplementary InfoJournalref: Nature Communications, 9, 2274, (2018)Subjects: Neurons and Cognition (qbio.NC); Disordered Systems and Neural Networks (condmat.disnn); Biological Physics (physics.bioph)
Global integration of information in the brain results from complex interactions of segregated brain networks. Identifying the most influential neuronal populations that efficiently bind these networks is a fundamental problem of systems neuroscience. Here we apply optimal percolation theory and pharmacogenetic interventions invivo to predict and subsequently target nodes that are essential for global integration of a memory network in rodents. The theory predicts that integration in the memory network is mediated by a set of lowdegree nodes located in the nucleus accumbens. This result is confirmed with pharmacogenetic inactivation of the nucleus accumbens, which eliminates the formation of the memory network, while inactivations of other brain areas leave the network intact. Thus, optimal percolation theory predicts essential nodes in brain networks. This could be used to identify targets of interventions to modulate brain function.
 [53] arXiv:1806.07909 (crosslist from grqc) [pdf, other]

Title: Black hole binaries: ergoregions, photon surfaces, wave scattering, and quasinormal modesComments: 13 pages, 11 figuresSubjects: General Relativity and Quantum Cosmology (grqc); High Energy Astrophysical Phenomena (astroph.HE); High Energy Physics  Theory (hepth); Fluid Dynamics (physics.fludyn)
The photon surface of isolated black holes is related to important aspects of black hole physics, such as strong lensing, absorption cross section of null particles and the way that black holes relax through quasinormal ringing. When two black holes are present  such as during the inspiral and merger events of interest for gravitationalwave detectors  the concept of a photon surface still exists, but its properties are basically unknown. With these applications in mind, we study here the photon surface of two different static black hole binaries. The first one is the MajumdarPapapetrou geometry describing two extremal, charged black holes in equilibrium, while the second one is the double sink solution of fluid dynamics, which describes (in a curvedspacetime language) two "dumb" holes. For the latter solution, we also characterize its dynamical response to external perturbations, and study how it relates to the photon surface structure. In addition, we compute the ergoregion of such spacetime and show that it does not coincide with the event horizon.
 [54] arXiv:1806.07925 (crosslist from quantph) [pdf]

Title: There Is No Action at a Distance in Quantum Mechanics, Spooky or OtherwiseAuthors: Stephen BoughnComments: 9 pagesSubjects: Quantum Physics (quantph); History and Philosophy of Physics (physics.histph)
I feel compelled to respond to the frequent references to spooky action at a distance that often accompany reports of experiments investigating entangled quantum mechanical states. Most, but not all, of these articles have appeared in the popular press. As an experimentalist I have great admiration for such experiments and the concomitant advances in quantum information and quantum computing, but accompanying claims of action at a distance are quite simply nonsense. Some physicists and philosophers of science have bought into the story by promoting the nonlocal nature of quantum mechanics. In 1964, John Bell proved that classical hidden variable theories cannot reproduce the predictions of quantum mechanics unless they employ some type of action at a distance. I have no problem with this conclusion. Unfortunately, Bell later expanded his analysis and mistakenly deduced that quantum mechanics and by implication nature herself are nonlocal. In addition, some of these articles present Einstein in caricature, a tragic figure who neither understood quantum mechanics nor believed it to be an accurate theory of nature. Consequently, the current experiments have proven him wrong. This is also nonsense.
 [55] arXiv:1806.07947 (crosslist from math.CA) [pdf, ps, other]

Title: Simply improved averaging for coupled oscillators and weakly nonlinear wavesAuthors: Molei TaoComments: Comments are welcomedSubjects: Classical Analysis and ODEs (math.CA); Computational Physics (physics.compph)
The long time effect of nonlinear perturbation to oscillatory linear systems can be characterized by the averaging method, and we consider firstorder averaging for its simplest applicability to highdimensional problems. Instead of the classical approach, in which one uses the pullback of linear flow to isolate slow variables and then approximate the effective dynamics by averaging, we propose an alternative coordinate transform that better approximates the mean of oscillations. This leads to a simple improvement of the averaged system, which will be shown both theoretically and numerically to provide a more accurate approximation. Three examples are then provided: in the first, a new device for wireless energy transfer modeled by two coupled oscillators was analyzed, and the results provide design guidance and performance quantification for the device; the second is a classical coupled oscillator problem (FermiPastaUlam), for which we numerically observed improved accuracy beyond the theoretically justified timescale; the third is a nonlinearly perturbed firstorder wave equation, which demonstrates the efficacy of improved averaging in an infinite dimensional setting.
 [56] arXiv:1806.07956 (crosslist from cs.SI) [pdf, other]

Title: Reconstructing networks with unknown and heterogeneous errorsAuthors: Tiago P. PeixotoComments: 27 pages, 17 figuresSubjects: Social and Information Networks (cs.SI); Learning (cs.LG); Data Analysis, Statistics and Probability (physics.dataan); Machine Learning (stat.ML)
The vast majority of network datasets contains errors and omissions, although this is rarely incorporated in traditional network analysis. Recently, an increasing effort has been made to fill this methodological gap by developing network reconstruction approaches based on Bayesian inference. These approaches, however, rely on assumptions of uniform error rates and on direct estimations of the existence of each edge via repeated measurements, something that is currently unavailable for the majority of network data. Here we develop a Bayesian reconstruction approach that lifts these limitations by not only allowing for heterogeneous errors, but also for individual edge measurements without direct error estimates. Our approach works by coupling the inference approach with structured generative network models, which enable the correlations between edges to be used as reliable error estimates. Although our approach is general, we focus on the stochastic block model as the basic generative process, from which efficient nonparametric inference can be performed, and yields a principled method to infer hierarchical community structure from noisy data. We demonstrate the efficacy of our approach with a variety of empirical and artificial networks.
 [57] arXiv:1806.08018 (crosslist from quantph) [pdf, other]

Title: Full characterization of a highdimensional quantum communication channelAuthors: Frédéric Bouchard, Felix Hufnagel, Dominik Koutný, Aazad Abbas, Alicia Sit, Khabat Heshami, Robert Fickler, Ebrahim KarimiComments: 7 pages, 4 figuresSubjects: Quantum Physics (quantph); Optics (physics.optics)
The characterization of quantum processes, e.g. communication channels, is an essential ingredient for establishing quantum information systems. For quantum key distribution protocols, the amount of overall noise in the channel determines the rate at which secret bits are distributed between authorized partners. In particular, tomographic protocols allow for the full reconstruction, and thus characterization, of the channel. Here, we perform quantum process tomography of highdimensional quantum communication channels with dimensions ranging from 2 to 5. We can thus explicitly demonstrate the effect of an eavesdropper performing an optimal cloning attack or an interceptresend attack during a quantum cryptographic protocol. Our study shows that the process matrix enables a more detailed understanding of the channel conditions compared to a coarsegrained measure, such as quantum bit error rates. This full characterization technique allows us to distinguish eavesdropping attempts and optimize the quantum key distribution performance under asymmetric experimental conditions.
 [58] arXiv:1806.08116 (crosslist from condmat.mtrlsci) [pdf]

Title: The structure of near stoichiometric GeGaSbS glasses: a reverse Monte Carlo studyAuthors: Ildikó Pethes, Virginie Nazabal, Radwan Chahal, Bruno Bureau, Ivan Kaban, Brigitte Beuneu, Jozef Bednarcik, Pál JóváriComments: 23 pages, 5 figures, submitted to Journal of Noncrystalline SolidsSubjects: Materials Science (condmat.mtrlsci); Disordered Systems and Neural Networks (condmat.disnn); Chemical Physics (physics.chemph)
The structure of Ge$_{22}$Ga$_3$Sb$_{10}$S$_{65}$ and Ge$_{15}$Ga$_{10}$Sb$_{10}$S$_{65}$ glasses was investigated by neutron diffraction (ND), Xray diffraction (XRD), and extended Xray absorption fine structure (EXAFS) measurements at the Ge, Ga and Sb Kedges. Experimental data sets were fitted simultaneously in the framework of the reverse Monte Carlo (RMC) simulation technique. Short range order parameters were determined from the obtained largescale configurations. It was found that the coordination numbers of Ge, Sb and S are around the values predicted by the Mottrule (4, 3 and 2, respectively). The Ga atoms have on average 4 nearest neighbors. The structure of these stoichiometric glasses can be described by the chemically ordered network model: GeS, GaS and SbS bonds are the most important. A distortion of Ge(Ga)S$_{4/2}$ and/or SbS$_{3/2}$ units can be observed in the form of long Ge(Ga)S and/or SbS distances (0.3  0.4 {\AA} higher than the usual covalent bond lengths).
 [59] arXiv:1806.08150 (crosslist from quantph) [pdf, other]

Title: The notion of locality in relational quantum mechanicsComments: 6 pages, 2 figuresSubjects: Quantum Physics (quantph); History and Philosophy of Physics (physics.histph)
The term 'locality' is used in different contexts with different meanings. There have been claims that relational quantum mechanics is local, but it is not clear then how it accounts for the effects that go under the usual name of quantum nonlocality. The present article shows that the failure of 'locality' in the sense of Bell, once interpreted in the relational framework, reduces to the existence of a common cause in an indeterministic context. In particular, there is no need to appeal to a mysterious spacelike influence to understand it.
 [60] arXiv:1806.08166 (crosslist from astroph.SR) [pdf, other]

Title: Testing Alfvén wave propagation in a realistic setup of the solar atmosphereAuthors: Piyali ChatterjeeComments: 17 pages, 8 figures, 1 table and 3 animation links (submitted to the Geophysical and Astrophysical Fluid dynamics special issue Algorithms and physics of the Pencil code)Subjects: Solar and Stellar Astrophysics (astroph.SR); Computational Physics (physics.compph)
We present a radiative magnetohydrodynamic simulation setup using the Pencil code to study the generation, propagation and dissipation of Alfv\'en waves in the solar atmosphere which includes a convective layer and photosphere below, and the chromosphere, transition region and the corona above. We outline the procedure to prepare the initial state where the solar convection has reached a steady state and the imposed external magnetic field has reached the final value, gradually increasing from a very small initial value. Any new simulation to study Alfv\'en wave propagation can be started from this state which has been thus prepared. We present first results about the nature of waves excited in this simulation run.
 [61] arXiv:1806.08219 (crosslist from condmat.mtrlsci) [pdf, ps, other]

Title: Growth evolution of selfaffine thermally evaporated KBr thin films: A fractal assessmentSubjects: Materials Science (condmat.mtrlsci); Instrumentation and Detectors (physics.insdet)
In this article, fractal concepts were used to explore the thermally evaporated potassium bromide thin films of different thicknesses 200, 300, and 500 nm respectively; grown on aluminium substrates at room temperature. The selfaffine or self similar nature of growing surfaces was investigated by autocorrelation function and obtained results are compared with the morphological envelope method. Theoretical estimations revealed that the global surface parameters such as, interface width and lateral correlation length are monotonically decreased with increasing film thickness. Also, from height profile and AF plots, it has been perceived that irregularity/ complexity of growing layers was significantly influenced by thickness. On the other hand, the fractal dimension and local roughness exponent, estimated by heightheight correlation function, do not suggest such dependency.
 [62] arXiv:1806.08332 (crosslist from cs.HC) [pdf]

Title: Towards Commodity, WebBased Augmented Reality Applications for Research and Education in Chemistry and Structural BiologyAuthors: Luciano A. AbriataComments: 8 pages, 6 figuresSubjects: HumanComputer Interaction (cs.HC); Emerging Technologies (cs.ET); Multimedia (cs.MM); Biological Physics (physics.bioph); Biomolecules (qbio.BM)
This article reports proofofconcept web apps that use commodity opensource technologies for augmented and virtual reality to tackle realworld problems from chemistry and structural biology. The apps include demonstrations of molecular visualization at atomistic and coarsegrained levels, coarsegrained modeling of molecular physics, onthefly calculation of experimental observables and comparison to actual data, and simulated chemical reactivity. Along the results and in the discussion section, future perspectives are depicted based on recent works in the areas of machine learning for chemistry, transcompilation of programs into JavaScript, and advanced APIs and libraries supported by major web browsers. Together, the developments presented and discussed in this article will certainly lead to the next generation of tools for truly interactive molecular modeling that can streamline human thought and intent with the numerical processing power of computers.
Replacements for Fri, 22 Jun 18
 [63] arXiv:1606.06111 (replaced) [pdf, ps, other]

Title: Deviations from universality in the fluctuation behavior of a heterogeneous complex system reveal intrinsic properties of components: The case of the international currency marketComments: 10 pages, 6 figures, final revised versionSubjects: Statistical Finance (qfin.ST); Physics and Society (physics.socph)
 [64] arXiv:1705.04472 (replaced) [pdf, other]

Title: Nonclassical light from large ensemble of trapped ionsAuthors: Petr Obšil, Lukáš Lachman, Tuan Pham, Adam Lešundák, V. Hucl, M.Čížek, Jan Hrabina, Ondřej Číp, Lukáš Slodička, Radim FilipJournalref: Phys. Rev. Lett. 120, 253602 (2018)Subjects: Quantum Physics (quantph); Atomic Physics (physics.atomph)
 [65] arXiv:1707.04120 (replaced) [pdf, ps, other]

Title: Simulating polaron biophysics with Rydberg atomsJournalref: Sci. Rep. 8, 9247 (2018)Subjects: Atomic Physics (physics.atomph); Quantum Gases (condmat.quantgas); Pattern Formation and Solitons (nlin.PS)
 [66] arXiv:1709.06615 (replaced) [pdf, other]

Title: Permutational symmetries for coincidence rates in multimode multiphotonic interferometryJournalref: Phys. Rev. A 97, 063802 (2018)Subjects: Quantum Physics (quantph); Optics (physics.optics)
 [67] arXiv:1710.05337 (replaced) [pdf, other]

Title: Observation of Laser Power Amplification in a SelfInjecting Laser Wakefield AcceleratorAuthors: M.J.V. Streeter, S. Kneip, M.S. Bloom, R.A. Bendoyro, O. Chekhlov, A.E. Dangor, A. Döpp, C.J. Hooker, J. Holloway, J. Jiang, N.C. Lopes, H. Nakamura, P.A. Norreys, C.A.J. Palmer, P.P. Rajeev, J. Schreiber, D.R. Symes, M. Wing, S.P.D. Mangles, Z. NajmudinComments: 6 pages, 4 figures. Published in PRLJournalref: Physical Review Letters 120, 254801 (2018)Subjects: Plasma Physics (physics.plasmph)
 [68] arXiv:1710.06833 (replaced) [pdf]

Title: Emission enhancement in dielectric nanocompositesJournalref: D. Jalas, K. Marvin Schulz, A. Yu. Petrov, and M. Eich, "Emission enhancement in dielectric nanocomposites," Opt. Express 26, 1635216364 (2018)Subjects: Optics (physics.optics)
 [69] arXiv:1710.07629 (replaced) [pdf, other]

Title: OpenFermion: The Electronic Structure Package for Quantum ComputersAuthors: Jarrod R. McClean, Ian D. Kivlichan, Kevin J. Sung, Damian S. Steiger, Yudong Cao, Chengyu Dai, E. Schuyler Fried, Craig Gidney, Brendan Gimby, Pranav Gokhale, Thomas Häner, Tarini Hardikar, Vojtěch Havlíček, Cupjin Huang, Josh Izaac, Zhang Jiang, Xinle Liu, Matthew Neeley, Thomas O'Brien, Isil Ozfidan, Maxwell D. Radin, Jhonathan Romero, Nicholas Rubin, Nicolas P. D. Sawaya, Kanav Setia, Sukin Sim, Mark Steudtner, Qiming Sun, Wei Sun, Fang Zhang, Ryan BabbushSubjects: Quantum Physics (quantph); Chemical Physics (physics.chemph); Computational Physics (physics.compph)
 [70] arXiv:1711.06904 (replaced) [pdf]

Title: A Study Concerning the Electronic Conductivity in Eumelanin Thin FilmsAuthors: Ludovico Migliaccio, Paola Manini, Carla Minarini, Paolo Tassini, Maria Grazia Maglione, Alessandro PezzellaComments: 4 pages; 4 figureSubjects: Applied Physics (physics.appph); Soft Condensed Matter (condmat.soft)
 [71] arXiv:1711.09132 (replaced) [pdf, other]

Title: Multiparameter Gaussian Quantum MetrologyComments: 14 pages, 3 figures; expanded and updated; to appear in Physical Review ASubjects: Quantum Physics (quantph); Statistical Mechanics (condmat.statmech); Mathematical Physics (mathph); Instrumentation and Detectors (physics.insdet); Optics (physics.optics)
 [72] arXiv:1712.01561 (replaced) [pdf, other]

Title: A new measure for community structures through indirect social connectionsSubjects: Social and Information Networks (cs.SI); Physics and Society (physics.socph)
 [73] arXiv:1802.08029 (replaced) [pdf, other]

Title: Optical Chirality of TimeHarmonic Wavefields for Classification of ScatterersComments: 13 pages, 4 figures; updated references [v2]; changed title, published in Sci. Rep. [v3]Journalref: Gutsche, P. & NietoVesperinas, M. Optical Chirality of TimeHarmonic Wavefields for Classification of Scatterers. Sci. Rep. 8, 9416 (2018)Subjects: Optics (physics.optics)
 [74] arXiv:1803.00461 (replaced) [pdf, other]

Title: Modeling the evolution and propagation of the 2017 September 9th and 10th CMEs and SEPs arriving at Mars constrained by remotesensing and insitu measurementAuthors: Jingnan Guo, Mateja Dumbović, Robert F. WimmerSchweingruber, Manuela Temmer, Henning Lohf, Yuming Wang, Astrid Veronig, Donald M. Hassler, Leila M. Mays, Cary Zeitlin, Bent Ehresmann, Oliver Witasse, Johan L. Freiherr von Forstner, Bernd Heber, Mats Holmström, Arik PosnerSubjects: Space Physics (physics.spaceph); Earth and Planetary Astrophysics (astroph.EP)
 [75] arXiv:1803.03942 (replaced) [pdf, other]

Title: Selforganized systemsize oscillation of a stochastic latticegas modelComments: added references; changed style of figures; added some more explanations; results unchangedSubjects: Biological Physics (physics.bioph); Statistical Mechanics (condmat.statmech); Subcellular Processes (qbio.SC)
 [76] arXiv:1803.04256 (replaced) [pdf, other]

Title: Evolving wormhole supported by dark matter and dark energyAuthors: Ali ÖvgünComments: 6 pages, two columnSubjects: General Physics (physics.genph)
 [77] arXiv:1804.01780 (replaced) [pdf, other]

Title: Calibration of the NEXTWhite detector using $^{83m}\mathrm{Kr}$ decaysAuthors: G. MartínezLema, J.A. Hernando Morata, B. Palmeiro, A. Botas, P. Ferrario, F. Monrabal, A. Laing, J. Renner, A. Simón, J.J. GómezCadenas, C. Adams, V. Álvarez, L. Arazi, C.D.R. Azevedo, K. Bailey, J.M. BenllochRodríguez, F.I.G.M. Borges, S. Cárcel, J.V. Carrión, S. Cebrián, C.A.N. Conde, J. Díaz, M. Diesburg, J. Escada, R. Esteve, R. Felkai, L.M.P. Fernandes, A.L. Ferreira, E.D.C. Freitas, J. Generowicz, A. Goldschmidt, D. GonzálezDíaz, R. Guenette, R.M. Gutiérrez, K. Hafidi, J. Hauptman, C.A.O. Henriques, A.I. Hernandez, V. Herrero, S. Johnston, B.J.P. Jones, M.Kekic, L. Labarga, P. Lebrun, N. LópezMarch, M. Losada, J. MartínAlbo, A. Martínez, A.D. McDonald, C.M.B. Monteiro, F.J. Mora, J. Muñoz Vidal, M. Musti, et al. (23 additional authors not shown)Comments: 20 pages, 18 figuresSubjects: Instrumentation and Detectors (physics.insdet); High Energy Physics  Experiment (hepex)
 [78] arXiv:1804.03479 (replaced) [pdf, other]

Title: Magnetohydrodynamics with GAMERComments: 29 pages, 22 figures, 1 table. GAMERMHD will soon become available at this https URLJournalref: The Astrophysical Journal supplement series, 236, 50, 2018Subjects: Computational Physics (physics.compph); Instrumentation and Methods for Astrophysics (astroph.IM)
 [79] arXiv:1804.05987 (replaced) [pdf, other]

Title: Direct computation of the quantum partition function by pathintegral nested samplingSubjects: Quantum Physics (quantph); Chemical Physics (physics.chemph); Computational Physics (physics.compph)
 [80] arXiv:1804.07488 (replaced) [pdf, other]

Title: Temporal Feedback Control of HighIntensity Laser Pulses to Optimize Ultrafast Heating of Atomic ClustersAuthors: M. J. V. Streeter, S. J. D. Dann, J. D. E. Scott, C. D. Baird, C. D. Murphy, S. Eardley, R. A. Smith, S. Rozario, J.N. Gruse, S. P. D. Mangles, Z. Najmudin, S. Tata, M. Krishnamurthy, S.V. Rahul, D. Hazra, P. Pourmoussavi, J. Hah, N. Bourgeois, C. Thornton, C. D. Gregory, C. J. Hooker, O. Chekhlov, S. J. Hawkes, B. Parry, V. A. Marshall, Y. Tang, E. Springate, P. P. Rajeev, A. G. R. Thomas, D. R. SymesComments: 5 pages, 3 figures, Published in APLJournalref: Appl. Phys. Lett. 112, 244101 (2018)Subjects: Plasma Physics (physics.plasmph)
 [81] arXiv:1806.00415 (replaced) [pdf]

Title: A Numerical Study of the Relationship Between Erectile Pressure and Shear Wave Speed of Corpus Cavernosa in Ultrasound VibroelastographyComments: 18 pages, 5 figures. 1 tableSubjects: Tissues and Organs (qbio.TO); Signal Processing (eess.SP); Medical Physics (physics.medph)
 [82] arXiv:1806.00725 (replaced) [pdf, other]

Title: Integrated Tempering Enhanced Sampling Method as the Infinite Switching Limit of Simulated TemperingComments: 9 pages, 3 figuresSubjects: Numerical Analysis (math.NA); Chemical Physics (physics.chemph); Computational Physics (physics.compph)
 [83] arXiv:1806.01989 (replaced) [pdf]

Title: Design of Voltage Pulse Control Module for Free Space MeasurementDeviceIndependent Quantum Key DistributionSubjects: Signal Processing (eess.SP); Emerging Technologies (cs.ET); Applied Physics (physics.appph)
 [84] arXiv:1806.02334 (replaced) [pdf]

Title: A Gravitational Wave TransmitterComments: 19 pagesSubjects: Popular Physics (physics.popph); General Relativity and Quantum Cosmology (grqc)
 [85] arXiv:1806.04082 (replaced) [pdf, other]

Title: Design a TDC in SiGe for RPC's electronics Frontend for the use in a highrate experimentAuthors: Salvatore Bruno, Roberto Cardarelli, Giulio Aielli, davide Badoni, Paolo Camarri, Anna Di Ciaccio, Eelio Alunno Camelia, Alessandro Caltabiano, Lorenzo Massa, Lorenzo Paolozzi, Luca Pizzimento, Alessandro RocchiComments: 7 pages, 11 figures, RPC conference 2018, JINST 2018Subjects: Instrumentation and Detectors (physics.insdet)
 [86] arXiv:1806.05150 (replaced) [pdf, other]

Title: Phaselocking between different partialwaves in atomion spinexchange collisionsAuthors: Tomas Sikorsky, Masato Morita, Ziv Meir, Alexei A. Buchachenko, Ruti Benshlomi, Nitzan Akerman, Edvardas Narevicius, Timur V. Tscherbul, Roee OzeriComments: 5 pages, 5 figures and Supplemental MaterialSubjects: Atomic Physics (physics.atomph); Quantum Gases (condmat.quantgas); Quantum Physics (quantph)
 [87] arXiv:1806.06138 (replaced) [pdf]

Title: Femtosecond laser inscription of nonlinear photonic circuits in Gallium Lanthanum Sulphide glassAuthors: María Ramos Vázquez, Belén Sotillo, Stefano Rampini, Vibhav Bharadwaj, Behrad Gholipour, Paloma Fernández, Roberta Ramponi, Cesare Soci, Shane M. EatonSubjects: Optics (physics.optics)
 [88] arXiv:1806.07451 (replaced) [pdf]

Title: Average individuals tweet more often during extreme events: An ideal mechanism for social contagionAuthors: Meredith T. Niles, Benjamin F. Emery, Andrew J. Reagan, Peter Sheridan Dodds, Christopher M. DanforthSubjects: Social and Information Networks (cs.SI); Physics and Society (physics.socph)
 [89] arXiv:1806.07479 (replaced) [pdf, other]

Title: Weight Thresholding on Complex NetworksSubjects: Physics and Society (physics.socph); Social and Information Networks (cs.SI)
 [90] arXiv:1806.07606 (replaced) [pdf, other]

Title: Toward theoretically limited SPP propagation length above two hundred microns on ultrasmooth silver surfaceAuthors: Aleksandr S. Baburin, Aleksey S. Kalmykov, Roman V. Kirtaev, Dmitriy V. Negrov, Dmitriy O. Moskalev, Ilya A. Ryzhikov, Pavel N. Melentiev, Ilya A. Rodionov, Victor I. BalykinSubjects: Optics (physics.optics); Materials Science (condmat.mtrlsci)
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