Distribution Function of Electron Velocity Perpendicular to the Driving Force in a Uniform Nonequilibrium Steady State
Abstract
A macroscopically uniform model of a two-dimensional electron system is proposed to study nonequilibrium properties of electrical conduction. By molecular dynamics simulation, the steady state distribution function Py of electron velocity in a direction perpendicular to an external driving force is calculated. An explicit form of Py is determined within the accuracy of the numerical simulation, which fits the numerical data well even in the regime where a local equilibrium description is not valid. Although the entire structure of Py is different from that of a local equilibrium distribution function, the asymptotic structure of the tails of Py in the limit of large absolute values of the velocity is identical to that of a Maxwell distribution function with a temperature which is different from that in the equilibrium state and the kinetic temperature in the steady state.