Charge Transport in a Spin-Polarized 2D Electron System in Silicon

TL;DR

This study investigates how the conductivity of a strongly interacting 2D electron system in silicon varies with temperature under zero and high magnetic fields, revealing differences in behavior related to spin polarization.

Contribution

It provides a detailed analysis of temperature-dependent conductivity in a spin-polarized 2D electron system, comparing experimental results with interaction correction theories.

Findings

Conductivity in zero field matches interaction correction theory.

In spin-polarized state, conductivity shows nonlinear and nonmonotonic behavior.

Low-temperature conductivity remains linear and consistent with theoretical predictions.

Abstract

The temperature dependences of the conductivity \sigma(T) for strongly interacting 2D electron system in silicon have been analyzed both in zero magnetic field and in spin-polarizing magnetic field of 14.2T, parallel to the sample plane. Measurements were carried out in a wide temperature range (1.4-9)K, in the ballistic regime of electron-electron interaction, i.e., for T\tau > 1. In zero magnetic field, the data obtained for \sigma(T) are quantitatively described by the theory of interaction corrections. In the fully spin-polarized state, the measured \sigma(T) dependences are nonlinear and even nonmonotonic for the same temperature range, where the \sigma(T) dependences are monotonic in the absence of the field. Nevertheless, the low-temperature parts of the experimental \sigma(T) dependences are linear and are qualitatively consistent with the calculated interaction corrections.