Low Temperature Physics: 44, 294 (2018); https://doi.org/10.1063/1.5030451
Fizika Nizkikh Temperatur: Volume 44, Number 4 (April 2018), p. 389-397    ( to contents , go back )

A two-dimensional electron crystal over liquid helium in the nonlinear mode. An analysis of resonance spectra of the electron-ripplon oscillations

V.E. Syvokon and I.V. Sharapova

B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Nauky Ave., Kharkiv 61103, Ukrain
E-mail: sivokon@ilt.kharkov.ua

Received October 20, 2017

Abstract

The spectrum of coupled electron-ripplon oscillations in the Wigner crystal is studied experimentally, depending on amplitude of the exciting signal. In-creasing the exciting voltage is found to cause the noticeable spectrum distortion and the shift of the resonances down to lower frequencies. Excitation of the non-axisymmetrical oscillations is found under of the spectra analysis. Because of radial symmetry of the cell and the exciting electrode a possible reason for such excitations may be the crystal lattice distortion. It is suggested under analysis that the electron-ripplon interaction contributes only in the electron effective mass renormalization.

PACS: 73.40.–c Electronic transport in interface structures;
PACS: 67.90.+z Other topics in quantum fluids and solids.

Key words: Wigner crystal, liquid helium, two-dimensional system, resonance spectra, electron-ripplon oscillations.

Published online: February 26, 2018

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