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arXiv:cond-mat/9401033 · Physical review. B, Condensed matter

Effective action of a (2+1)-dimensional system of nonrelativistic fermions in the presence of a uniform magnetic field: Dissipation effects

S. Sakhi

Published May 15, 1994• 7 citations
arXivHTMLPDF

Abstract

The effective action of nonrelativistic fermions in 2+1 dimensions is analyzed at finite temperature and chemical potential in the presence of a uniform magnetic field perpendicular to the plane. The method used is a generalization of the derivative expansion technique. The induced Chern-Simons term is computed and shown to exhibit Hall quantization. Effects of dissipation due to collisions are also analyzed.

DOI
10.1103/physrevb.49.13691

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The effective action of nonrelativistic fermions in 2+1 dimensions is analyzed at finite temperature and chemical potential in the presence of a uniform magnetic field perpendicular to the plane. The method used is a generalization of the derivative expansion technique. The induced Chern-Simons term is computed and shown to exhibit Hall quantization. Effects of dissipation due to collisions are also analyzed.
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We present a nonperturbative computation of the equation of state of polarized, attractively interacting, nonrelativistic fermions in one spatial dimension at finite temperature. We show results for the density, spin magnetization, magnetic susceptibility, and Tan's contact. We compare with the second-order virial expansion, a next-to-leading-order lattice perturbation theory calculation, and interpret our results in terms of pairing correlations. Our lattice Monte Carlo calculations implement an imaginary chemical potential difference to avoid the sign problem. The thermodynamic results on the imaginary side are analytically continued to obtain results on the real axis. We focus on an intermediate- to strong-coupling regime, and cover a wide range of temperatures and spin imbalances.
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