Acoustoelectric current for composite fermions

TL;DR

This paper calculates the acoustelectric current for composite fermions in a 2DEG near half-filling, revealing deviations from the Weinreich relation caused by Chern-Simons field effects, which can inform on composite fermion properties.

Contribution

It introduces a detailed calculation of the acoustelectric current considering the Chern-Simons field, highlighting deviations from classical relations in composite fermion systems.

Findings

Oscillating Chern-Simons field significantly affects the acoustelectric current.

Deviations from the Weinreich relation can be experimentally detected.

Additional insights into composite fermion fluid properties are obtained.

Abstract

The acoustelectric current for composite fermions in a two-dimensional electron gas (2DEG) close to the half-filled Landau level is calculated in the random phase approximation. The Boltzmann equation is used to find the nonequilibrium distribution of composite fermions to second order in the acoustic field.It is shown that the oscillating Chern-Simons field created by the induced density fluctuations in the 2DEG is important for the acoustoelectric current. This leads to a violation of the Weinreich relation between the acoustoelectric current and acoustic intensity. The deviations from the Weinreich relation can be detected by measuring the angle between the longitudinal and the Hall components of the acoustoelectric current. This departure from the Weinreich relation gives additional information on the properties of the compostite fermion fluid.