The absorption coefficient for surface acoustic waves in a piezoelectric insulator in contact with a GaAs/AlGaAs heterostructure (with two-dimensional electron mobility μ=1.3×105cm2/V⋅s) at T=4.2K) via a small gap has been investigated experimentally as a function of the frequency of the wave, the width of the vacuum gap, the magnetic field, and the temperature. The magnetic field and frequency dependencies of the high-frequency conductivity (in the region 30-210 MHz) are calculated and analyzed. The experimental results can be explained if it assumed that there exists a fluctuation potential in which current carrier localization occurs. The absorption of the surface acoustic waves in an interaction with two-dimensional electrons localized in the energy "tails" of Landau levels is discussed.
@article{arxiv.cond-mat/9910450,
title = {Electron localization in sound absorption oscillations in the quantum Hall effect regime},
author = {I. L. Drichko and A. M. Diakonov and A. M. Kreshchuk and T. A. Polyanskaya and I. G. Savel'ev and I. Yu. Smirnov and A. V. Suslov},
journal= {arXiv preprint arXiv:cond-mat/9910450},
year = {2009}
}