Dynamics of Spontaneous Electric Field Domains in a Two-Dimensional Electron System Irradiated by Microwaves and the Conductance of a Donor Layer

The temperature dependence of the switching frequency of a microwave-induced spontaneous electric field forming a domain structure and the conductance of a doping layer that provides electrons to the two-dimensional electron system have been measured on samples fabricated from the same GaAs/AlGaAs heterostructure. Both quantities have been found to obey the thermally activated dependence (Arrhenius law) with close activation energies. This result indicates a relation between the quantities and confirms a hypothesis that the observed dynamics of the domain structure originates from the dynamical screening of the spontaneous electric field of domains by charges in the doping layer.     

Dynamics of the Photoinduced Rotation of a Spherical Particle in a Constant Electric Field

Technical Physics - The rotation of a spherical particle in a constant electric field (an effect found earlier) has been analyzed. The particle is illuminated to induce the electric dipole moment...     

Diffusion Dynamics of Rydberg States in the Field of Radiation with Continuous Spectrum

Optics and Spectroscopy - Redistribution of population of Rydberg states and ionization of an atom as a result of multistep cascade transitions between states induced by radiation with continuous...     

Dissipation in the Klein-Gordon Field

The formalism of (±)-frequency parts , previously applied to solution of the D'Alembert equation in the case of the electromagnetic field, is applied to solution of the Klein-Gordon equation for the K-G field in the presence of sources. Retarded and advanced field operators are obtained as solutions, whose frequency parts satisfy a complex inhomogeneous K-G equation. Fourier transforms of these frequency parts are solutions of the central equation, which determines the time dependence of the destruction/creation operators of the field. The retarded field operator is resolved into kinetic and dissipative components. Correspondingly, the energy/stress tensor is resolved into three components; the power/force density, into two—a kinetic and a dissipative component. As in the analogous electromagnetic case the dissipation theorem is derived according to which work done by the dissipative power/force is negative: energy/momentum is dissipated from the sources to the K-G field. Boson quantization conditions are satisfied by the kinetic component but not by the dissipative component of the retarded K-G field.     

Superposition of Coherent States in a Mesoscopic Josephson Junction with Dissipation

A mesoscopic Josephson junction with dissipation is considered. Usually the dissipation in the system is described as a consequence of its coupling to a reservoir. By solving the master equation we show that the state of the junction can evolve in a quantum superposition of two coherent states even when the dissipation is present.     

Superposition of Coherent States in a Mesoscopic Josephson Junction with Dissipation

A mesoscopic Josephson junction with dissipation is considered. Usually the dissipation in the system is described as a consequence of its coupling to a reservoir. By solving the master equation we show that the state of the junction can evolve in a quantum superposition of two coherent states even when the dissipation is present.``     

Electric Field in a Gravitational Field

The potential of a static electric charge located in a Schwarzschild gravitational field is given by Linet. The expressions for the field lines derived from this potential are calculated by numerical integration and drawn for different locations of the static charge in the gravitational field. The field lines calculated for a charge located very close to the central mass can be compared to those calculated by Hanni–Ruffini. Maxwell equations are used to analyze the dynamics of the falling electric field in a gravitational field.     

Evolution of Arbitrary States under Fock-Darwin Hamiltonian and a Time-Dependent Electric Field

The method of path integral is employed to calculate the time evolution of the eigenstates of a charged particle under the Fock-Darwin(FD) Hamiltonian subjected to a time-dependent electric field in the plane of the system.An exact analytical expression is established for the evolution of the eigenstates.This result then provides a general solution to the time-dependent Schro¨dinger equation.     

Effects of Electric Field on Electronic States in a GaAs/GaAlAs Quantum Dot with Different Confinements

Binding energies of shallow hydrogenic impurity in a GaAs/GaAlAs quantum dot with spherical confinement, parabolic confinement and rectangular confinement are calculated as a function of dot radius in the influence of electric field. The binding energy is calculated following a variational procedure within the effective mass approximation along with the spatial depended dielectric function. A finite confining potential well with depth is determined by the discontinuity of the band gap in the quantum dot and the cladding. It is found that the contribution of spatially dependent screening effects are small for a donor impurity and it is concluded that the rectangulax confinement is better than the parabolic and spherical confinements. These results are compared with the existing literature.     

Quantum States of a Neutral Massive Fermion with an Anomalous Magnetic Moment in an External Electric Field

The quantum dynamics of a nonrelativistic neutral massive fermion with an anomalous magnetic moment (AMM) is examined in the external electric field of an infinitely long thin homogeneously charged thread in the plane with a normal directed along the thread. The Hamiltonian of the Dirac–Pauli equation for a neutral fermion with AMM is essentially singular in the considered external field and requires a supplementary extension of the definition in order for it to be treated as a self-adjoint quantum-mechanical operator. All one-parameter self-adjoint extensions of the Hamiltonian of the Dirac–Pauli equation in the considered external field are found in the nonrelativistic approximation. The corresponding Hilbert space of squareintegrable functions, including a singularity point of the Hamiltonian, is specified for each self-adjoint extension of the Hamiltonian. The wave functions of free and bound states, as well as discrete energy levels, are determined by the self-adjoint extension method and their correspondence with similar quantities obtained by the physical regularization procedure is discussed. It is shown that energy levels of bound states are simple poles of the scattering amplitude, which should be extended in definition by introducing the self-adjoint extension parameter into it. Expressions for the scattering amplitude and cross-section, depending on the orientation of the initial-state spin of fermion, are obtained.     

均匀电场SF6短气隙放电过程动态模拟

根据基本物理定律和流体力学,构建均匀电场下SF₆短气隙放电流体模型,运用通量校正传输法(flux-corrected transport)数值分析大气压下4 mm间隙SF₆的放电过程,展现放电空间带电粒子产生、复合、附着、扩散以及光致电离动态过程,获得了放电间隙电场畸变、带电粒子动力学行为和放电通道形成发展历程和时空分布,根据R-M判据求出模型放电过程中电子崩转向流注的时空临界点,印证了光致电离在流注发展阶段的重要作用.     

Quantum Problem on the Dynamics of an Electric Charge in Its Own Field

Physics of Particles and Nuclei Letters - In this paper we study the dynamics of a charge interacting with its own field in the one-dimensional case and in the spherically symmetric...     

Exciton States in ZnO/MgZnO Quantum Wells under Electric Field and Magnetic Field

Physics of the Solid State - Zinc oxide (ZnO) and related alloys are regarded as competitive materials for blue and ultraviolet optoelectronic devices, widely used in commercial and military areas...     

电场下液滴合并自弹跳行为的分子动力学研究

在工程上通常利用滴状冷凝提高冷凝换热效率、进而强化传热.而当冷凝液滴发生合并自弹跳时,冷凝换热系数是传统滴状冷凝的1.3至1.5倍,因此液滴合并自弹跳现象对冷凝传热强化的贡献是非常大的.一些宏观实验和理论研究表明,加入外电场能进一步促进冷凝液滴合并自弹跳的频率和高度,但在纳米尺度下是否仍遵守这一规律还未可知,因此本文使...     

Eu原子偶宇称高激发态的场电离探测

利用共振激发技术和电场电离(EFI)方法研究了铕(Eu)原子偶宇称高激发态。实验共探测到89个态,其中报道了56个态的能级位置和光谱归属等信息。经过对有效主量子数和量子亏损进行理论分析,并结合文献结果的对比,不但认定它们属于4f76s(9S)np(8PJ或10PJ)里德伯系列,还填补了该系列中n=19～39各态的文献空白。另外,建议将Eu原子第一电离限修正为45734.2cm-1,同时解释了在其附近所观察到的宽峰的物理机制。     

Dynamics of Electronic States and Magnetoabsorption in 3D Topological Insulators in a Quantizing Magnetic Field

Quantum states have been calculated analytically; the dynamics of a wave packet in a magnetic field has been investigated, and the optical absorption coefficient has been calculated for surface states in 3D topological insulators of the Bi₂Te₃ family. We have detected a qualitative effect of the hexagonal warping of the spectrum on the structure of wavefunctions at the Landau levels, its manifestation in the features of the wave packet dynamics in a quantizing magnetic field, as well as in the frequency dependence of the optical absorption coefficient, in which new peaks that are absent in the isotropic model of the spectrum appear depending on the polarization of the incident wave. The effects considered here can be manifested in the optical and transport experiments with topological insulators, which makes it possible to determine the parameters of their band structure.     

Information Dynamics of Electric Field Intensity before and during the COVID-19 Pandemic

This work investigates the temporal statistical structure of time series of electric field (EF) intensity recorded with the aim of exploring the dynamical patterns associated with periods with different human activity in urban areas. The analyzed time series were obtained from a sensor of the EMF RATEL monitoring system installed in the campus area of the University of Novi Sad, Serbia. The sensor performs wideband cumulative EF intensity monitoring of all active commercial EF sources, thus including those linked to human utilization of wireless communication systems. Monitoring was performed continuously during the years 2019 and 2020, allowing us to investigate the effects on the patterns of EF intensity of varying conditions of human mobility, including regular teaching and exam activity within the campus, as well as limitations to mobility related to the COVID-19 pandemic. Time series analysis was performed using both simple statistics (mean and variance) and combining the information-theoretic measure of information storage (IS) with the method of surrogate data to quantify the regularity of EF dynamic patterns and detect the presence of nonlinear dynamics. Moreover, to assess the possible coexistence of dynamic behaviors across multiple temporal scales, IS analysis was performed over consecutive observation windows lasting one day, week, month, and year, respectively coarse grained at time scales of 6 min, 30 min, 2 h, and 1 day. Our results document that the EF intensity patterns of variability are modulated by the movement of people at daily, weekly, and monthly scales, and are blunted during periods of restricted mobility related to the COVID-19 pandemic. Mobility restrictions also affected significantly the regularity of the EF intensity time series, resulting in lower values of IS observed simultaneously with a loss of nonlinear dynamics. Thus, our analysis can be useful to investigate changes in the global patterns of human mobility both during pandemics or other types of events, and from this perspective may serve to implement strategies for safety assessment and for optimizing the design of networks of EF sensors.