Interaction-induced magnetoresistance in a two-dimensional electron gas

TL;DR

This paper develops a comprehensive theory for how electron-electron interactions affect magnetoresistance in two-dimensional electron gases across various regimes of temperature, disorder, and magnetic field, revealing new quantum oscillation phenomena.

Contribution

The authors introduce a general formalism using classical propagators to calculate interaction-induced conductivity corrections in diverse conditions, including anisotropic systems and superlattices.

Findings

Interaction causes quantum corrections to conductivity tensor in 2D electron gases.

The formalism applies across diffusive and ballistic regimes, with different disorder types.

Novel quantum oscillations in resistivity are predicted for lateral superlattices.

Abstract

We study the interaction-induced quantum correction \delta\sigma_{\alpha\beta} to the conductivity tensor of electrons in two dimensions for arbitrary T\tau (where T is the temperature and \tau the transport scattering time), magnetic field, and type of disorder. A general theory is developed, allowing us to express \delta\sigma_{\alpha\beta} in terms of classical propagators (``ballistic diffusons''). The formalism is used to calculate the interaction contribution to the longitudinal and the Hall resistivities in a transverse magnetic field in the whole range of temperature from the diffusive (T\tau << 1) to the ballistic (T\tau > 1) regime, both in smooth disorder and in the presence of short-range scatterers. Further, we apply the formalism to anisotropic systems and demonstrate that the interaction induces novel quantum oscillations in the resistivity of lateral superlattices.