Spin Degree of Freedom in a Two-Dimensional Electron Liquid

TL;DR

This study explores how spin polarization affects magnetotransport in a high mobility silicon electron system, revealing a link between magnetic field, electron spin states, and resistivity near the metal-insulator transition.

Contribution

It demonstrates the correlation between spin polarization and resistivity saturation, providing new insights into spin effects in two-dimensional electron liquids.

Findings

Resistivity saturates at a critical magnetic field for full spin polarization.

Normal magnetic field component at resistivity minima increases linearly with spin-up electron concentration.

Full spin polarization occurs at a specific magnetic field strength.

Abstract

We have investigated correlation between spin polarization and magnetotransport in a high mobility silicon inversion layer which shows the metal-insulator transition. Increase in the resistivity in a parallel magnetic field reaches saturation at the critical field for the full polarization evaluated from an analysis of low-field Shubnikov-de Haas oscillations. By rotating the sample at various total strength of the magnetic field, we found that the normal component of the magnetic field at minima in the diagonal resistivity increases linearly with the concentration of ``spin-up'' electrons.