Cyclotron resonance of polarons confined to a surface

Abstract

Corrections to the cyclotron resonance energy induced by electron---LO-phonon interaction for electrons confined to a heterojunction with magnetic field perpendicular to the surface are calculated. A weak Fr\"olich interaction with bulk LO phonons is assumed, and correlation due to the Coulomb repulsion of the electrons is neglected. Various approximations are compared for the two-dimensional polaron in the zero-density limit. The transition from two-dimensional to bulk behavior is studied, and an approximate method of calculation for an arbitrary confining potential is proposed and tested. Corrections to the cyclotron-resonance energy due to nonzero electron density are calculated by summing the "most divergent" terms in perturbation theory to all orders. It is suggested that correlation may be important for electrons in full or nearly full Landau levels.