Kinetics of a quasi-one-dimensional electron gas in a transverse magnetic field: Quantum transport equations and screening.

Abstract

The quantum kinetic equation for the one-electron distribution function is derived from first principles for a quasi-one-dimensional electron gas in a transverse magnetic field B. The screening of the scattering potentials (impurities, phonons, etc.) is treated dynamically and self-consistently in a manner equivalent to the random-phase approximation and the collision integrals are expressed in terms of the dielectric function and the potential correlators. The momentum and energy-balance equations are derived as well. For weak fields and within the drifted-temperature model they lead to explicit expressions for the corresponding relaxation frequencies. The latter are evaluated analytically when only the lowest subband is occupied for scattering by volume or sheet long-range impurities, by point-line impurities, and by acoustical phonons. The conductivity behaves in a nontrival way as function of B and at certain values of B it vanishes corresponding to the depopulation of the level.