Structural transitions and plasma oscillations in electron rows above liquid helium
V.E. Syvokon, S.S. Sokolov, 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, Ukraine
Received June 25, 2018, published online November 26, 2018
A two-dimensional Wigner crystal formed by electrons located above a rectangular electrode with uniformly distributed positive charge, is studied by the molecular dynamics method. We analyze the possible electron configurations over a narrow electrode at the fixed electron density, depending on the width of the electrode. Also the specifics of transitions between the configurations are studied. Electron configurations consisting of several rows are considered. After Fourier transformation of the time dependencies of the mean electrons’ coordinates is applied to model the plasma oscillations spectra. The frequencies of plasma oscillations estimated at the modeling are compared with those calculated theoretically for one and two rows.
Key words: Wigner crystal, superfluid helium, two-dimensional system, electronic chainlets, plasma oscillations spectra, simulation.