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arXiv:cond-mat/0511668 · Physical Review B

Spin susceptibility of a two-dimensional electron system in GaAs towards the weak interaction region

Yan‐Wen Tan, Jun Zhu, Horst L. Stormer, Loren N. Pfeiffer, K. W. Baldwin, K. W. West

Published Jan 31, 2006• 23 citations
arXivHTMLPDF

Abstract

We determine the spin susceptibility $\ensuremath{\chi}$ in the weak interaction regime of a tunable, high quality, two-dimensional electron system in a $\mathrm{Ga}\mathrm{As}∕\mathrm{Al}\mathrm{Ga}\mathrm{As}$ heterostructure. The band structure effects, modifying mass and $g$-factor, are carefully taken into accounts since they become appreciable for the large electron densities of the weak interaction regime. When properly normalized, $\ensuremath{\chi}$ decreases monotonically from 3 to 1.1 with increasing density over our experimental range from 0.1 to $4\ifmmode\times\else\texttimes\fi{}{10}^{11}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}2}$. In the high density limit, $\ensuremath{\chi}$ tends correctly towards $\ensuremath{\chi}\ensuremath{\rightarrow}1$ and compare well with recent theory.

DOI
10.1103/physrevb.73.045334

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We present numerical calculations of the effect of electron-electron interactions on the quasiparticle properties such as the effective mass and the Land\'e ggg-factor in a GaAs∕AlGaAs\mathrm{Ga}\mathrm{As}∕\mathrm{Al}\mathrm{Ga}\mathrm{As}GaAs∕AlGaAs triangular quantum well from which the spin susceptibility is obtained. For this purpose, we consider quantum many-body effects associated with charge- and spin-density fluctuations induced many-body vertex corrections. The approach is based on the many-body local-field factors which are extracted from Fermi hypernetted-chain self-consistent calculation through the fluctuation-dissipation theorem. We find the spin susceptibility in good agreement with the recent experimental measurements and quantum Monte Carlo simulation data for such a system in the weak and intermediate coupling limits.
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