Absorption of Microwave Radiation by Bernstein Magnetoplasmon Modes in Inhomogeneous Two-Dimensional Electronic Systems

Abstract

A study is performed of microwave absorption in inhomogeneous two-dimensional electron systems characterized by a finite size or by a modulation of parameters. Experiments and calculations are compared to show that resonance maxima in absorption are observed at the frequencies of Bernstein modes corresponding to the characteristic wave vector of inhomogeneity k. At low k, the absorption maxima at the second harmonic of the cyclotron resonance are observed in addition to the main resonance at the frequency of cyclotron magnetoplasmon with wave vector k. At high k corresponding to condition $k{{R}_{{\text{c}}}} > 1,$ the position of the resonant absorption are parameterized in coordinates ($k{{R}_{{\text{c}}}},~\,\,{{{\omega }} \mathord{\left/ {\vphantom {{{\omega }} {{{{{\omega }}}_{{\text{c}}}}}}} \right. \kern-0em} {{{{{\omega }}}_{{\text{c}}}}}}$), where ${{{{\omega }}}_{{\text{c}}}}$ is the cyclotron frequency, ${{R}_{{\text{c}}}}$ is the cyclotron radius of an electron, and ω is the circular frequency of radiation.