Electron-LO-Phonon Intrasubband Scattering Rates near a Cylindrical Cavity; Axial Applied Magnetic Field

Abstract

The electron-LO-phonon intrasubband scattering rates near a cylindrical cavity are calculated as functions of the axial applied magnetic field and the electric potential of the heterostructure. Anticipating the confinement of phonons to be rather weak, scattering of electrons is assumed to be via bulk phonon modes. The electron's energy subbands are obtained within the effective-mass approximation. An increase of the magnetic field leads to the lowest-order electron's energy subbands taking turns at becoming the ground state, following the sequence {m = 0, -1, -2 ... -N} of azimuthal quantum numbers. This is a direct consequence of the presence of a hole which, for infinite walls of the potential, is a forbidden region for the motion of the electrons. A given value of the magnetic field therefore selects a particular electron's energy subband for the ground-state intrasubband scattering process. The main prediction of these investigations is the considerable enhancement of the intrasubband scattering rates for a very small radius of the cavity.