Spin susceptibility and polarization field in a dilute two-dimensional electron system in (111) silicon

TL;DR

This study investigates the spin susceptibility and polarization fields in a dilute two-dimensional electron system in (111) silicon, revealing how these properties evolve with electron density and subband filling.

Contribution

It provides new insights into the relationship between polarization fields and spin susceptibility, especially regarding subband filling effects in (111) silicon.

Findings

Polarization field B_chi correlates with strong spin susceptibility growth at low densities.

B_sat deviates from B_chi at higher densities due to subband filling.

Spin susceptibility increases significantly as electron density decreases.

Abstract

We find that the polarization field, B_chi, obtained by scaling the weak-parallel-field magnetoresistance at different electron densities in a dilute two-dimensional electron system in (111) silicon, corresponds to the spin susceptibility that grows strongly at low densities. The polarization field, B_sat, determined by resistance saturation, turns out to deviate to lower values than B_chi with increasing electron density, which can be explained by filling of the upper electron subbands in the fully spin-polarized regime.