The hodograph method in electrodynamics of continuous nonlinearly conducting media PMM vol. 31, no. 6, 1967, pp. 1077–1080

In a wide class of conductors, the presence of strong electric fields disrupts the linearity of the relationship between the current density and the electric field strength. Plasma and semiconductors exhibit the most observable deviations from the Ohm's law. This lack of linearity results from the fact that the current carriers assume nonequilibrium states. During the collisions, the electrons transfer their energy to the ions, molecules e.t.c. relatively slow because of their small mass. At the same time, they possess arbitrarily large free paths and can, therefore absorb large amount of energy from the electric field between successive collisions. Thus their temperature may differ appreciably from the equilibrium temperature due to the heating effect of the field.

Since initial equations are nonlinear, we may experience a difficulty in determining the current distribution in media with these properties. However, using the hodograph transformation we can linearise the electrodynamic equations. This, and use of approximate methods, give us an effective procedure tor computing the electric fields in nonlinearly conducting media.     

Dependence of equilibrium properties of channeled particles on the transverse quasitemperature

We use methods of nonequilibrium thermodynamics to investigate the quasiequilibrium and kinetic characteristics of channeled particles regarded as a separate thermodynamic subsystem. For the channeled particles, we derive the energy—momentum balance equation in the moving coordinate system and show that the solution of the balance equation provides an expression for the main thermodynamic parameter, the transverse quasitemperature of the channeled-particle subsystem. We study the quasiequilibrium angular distribution of particles after their passage through a thin single crystal, the quasiequilibrium distribution over the particle exit angles under backscattering conditions, and also the rate constant for the nonequilibrium (dechanneling) process at large deviations of the system as a whole from the thermodynamic equilibrium. We discuss a measurement method for the particle beam transverse temperature over the peak height of the angular particle distribution found in the framework of a “shoot-through” experiment. __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 146, No. 3, pp. 509–524, March, 2006.     

周期壁面电势调制下平行板微管道中的电磁电渗流动

研究了平行板微管道中二维磁流体(MHD)电渗流(EOF)在zeta电势调制下的流动.流体的流动是由两个外加水平电场和垂直磁场所产生的Lorentz力和电场力的组合驱动的.在滑移边界条件下,得到了流函数以及速度分布的解析解.详细讨论了速度随Hartmann数Ha、滑移长度B、电动宽度K等相关的无量纲参数量级变化的变化规律.结果表明,调制的壁面电势会产生一个垂直速度分量,从而导致涡旋的形成.此外,可以观察到,速度的大小随着滑移长度B和电动宽度K的增大而增大.值得注意的是,速度的大小随着Ha值的增大而减小,这与一维流动中Ha值存在临界值的情况不同.     

Memory Effects and Nonequilibrium Correlations in the Dynamics of Open Quantum Systems

We propose a systematic approach to the dynamics of open quantum systems in the framework of Zubarev’s nonequilibrium statistical operator method. The approach is based on the relation between ensemble means of the Hubbard operators and the matrix elements of the reduced statistical operator of an open quantum system. This key relation allows deriving master equations for open systems following a scheme conceptually identical to the scheme used to derive kinetic equations for distribution functions. The advantage of the proposed formalism is that some relevant dynamical correlations between an open system and its environment can be taken into account. To illustrate the method, we derive a non-Markovian master equation containing the contribution of nonequilibrium correlations associated with energy conservation.     

Die Bestimmung von Halbleiterparametern in Ge-PIN-Detektoren mit der Elektronensonde

Summary In this paper we report the use of the scanning electron beam technique for a measurement of the ambipolar diffusion length, the surface recombination velocity and the electric field distribution in Ge-Li-PIN-Diodes. A simple relation between the diffusion length and the photovoltage induced by the electron beam is derived. The diffusion length as a function of temperature shows a strong increase with decreasing temperature. This fact limits our method to temperatures above –80°C. A measurement of the electric field distribution is demonstrated for the case of double injection in PIN-Diodes with an extended intrinsiczone. The conductivity modulation caused by the electron beam, at constant current in forward direction, results in a change in the terminal voltage which is proportional to the square of the electric field strength at the injection point.     

On the convergence toward nonequilibrium stationary states in thermostatted kinetic models

A differential equation‐based framework is suitable for the modeling of nonequilibrium complex systems if its solution is able to reach, as time goes to infinity, the related nonequilibrium steady states. The thermostatted kinetic theory framework has been recently proposed for the modeling of complex systems subjected to an external force field. The present paper is devoted to the mathematical proof of the convergence of the solutions of the thermostatted kinetic framework towards the related nonequilibrium stationary states. The proof of the main result is gained by employing the Fourier transform and distribution theory arguments.     

Heat Bounds and the Blowtorch Theorem

We study driven systems with possible population inversion and we give optimal bounds on the relative occupations in terms of released heat. A precise meaning to Landauer’s blowtorch theorem (Phys Rev A 12:636–638, 1975) is obtained stating that nonequilibrium occupations are essentially modified by kinetic effects. Towards very low temperatures we apply a Freidlin-Wentzel type analysis for continuous time Markov jump processes. It leads to a definition of dominant states in terms of both heat and escape rates.     

Statistical hydrodynamics of magnetic fluids. I. the nonequilibrium statistical operator method

The Zubarev nonequilibrium statistical operator is used to describe the generalized hydrodynamic state of a magnetic fluid in an external magnetic field. The magnetic fluid is modeled with “liquid-state” and “magnetic” subsystems described using the classical and quantum statistics methods respectively. Equations of the generalized statistical hydrodynamics for a magnetic fluid in a nonhomogeneous external magnetic field with the Heisenberg spin interaction are derived for “liquid-state” and “magnetic” subsystems characterized by different nonequilibrium temperatures. These equations can be used to describe both the weakly and strongly nonequilibrium states. Some limiting cases are analyzed in which the variables of one of the subsystems can be formally neglected. Translated from Teoreticheskaya i Matematicheskaya Fizika. Vol. 115, No. 1, pp. 132–153, April, 1998.     

Existence of Majorana Bound States in A Superconducting Nanowire Near an Impurity

We consider a nanowire with the s-wave superconducting order induced as a result of the proximity effect in the presence of the Zeeman field and the Rashba interaction. For a small superconducting gap and small momenta, we analytically prove the existence of Majorana bound states for a certain local change in the Zeeman field or the superconducting order and also obtain explicit expressions for the corresponding wave functions. We study the scattering of excited states with energies that are close to boundary gap points in the case of propagation through an impurity for local changes in the indicated system parameters near this impurity and show that the transmission probability is equal to unity.