Conductivity of 2D many-component electron gas, partially-quantized by magnetic field

TL;DR

This paper investigates the electrical conductivity of a two-dimensional semimetal with heavy holes and light electrons under a magnetic field, revealing non-vanishing corrections at zero temperature due to Landau level degeneracy.

Contribution

It introduces a kinetic equation approach to analyze inter-component friction effects in a partially-quantized 2D electron-hole system, highlighting non-zero conductivity corrections at zero temperature.

Findings

Inter-component friction correction to conductivity does not vanish at zero temperature.

Landau level crossing by the Fermi level causes conductivity corrections.

Limits of kinetic equation applicability are identified.

Abstract

The 2D semimetal consisting of heavy holes and light electrons is studied. The consideration is based on assumption that electrons are quantized by magnetic field while holes remain classical. We assume also that the interaction between components is weak and the conversion between components is absent. The kinetic equation for holes colliding with quantized electrons is utilized. It has been stated that the inter-component friction and corresponding correction to the dissipative conductivity $\sigma_{xx}$ {\it do not vanish at zero temperature} due to degeneracy of the Landau levels. This correction arises when the Fermi level crosses the Landau level. The limits of kinetic equation applicability were found. We also study the situation of kinetic memory when particles repeatedly return to the points of their meeting.