Beating of the oscillations in the magnetocapacitance of a MODFET with Rasba spin–orbit interaction

Abstract

The effect of Rasba spin–orbit interaction (SOI) on the magnetocapacitance of the 2DEG in a MODFET is investigated. We present calculations on the density of states (DOS) of the 2DEG in a MODFET under the influence of both Rasba SOI and weak two-dimensional periodic modulation. Adopting a Gaussian broadening of magnetic-field-dependent width, we present a simple expression for the DOS, valid for the relevant weak magnetic fields and modulation strengths. In the presence of Rasba SOI and for weak potential modulation strengths, a typical beating pattern of the magnetocapacitance oscillations is observed in the low magnetic filed range. A simple relation that predicts the positions of nodes in the beating patterns is obtained. The interplay between the SOI and the periodic potential modulation is discussed.