Magnetopolarons in a polar-crystal slab are studied in the situation of weak electron-phonon coupling and a weak external magnetic field. The interactions between the electron and the bulk longitudinal-optical phonon and between the electron and the surface-optical phonon are included in this work. Formulas for the magnetopolaron energy levels in the slab are obtained by a perturbation method. The magnetopolaron cyclotron frequency is calculated numerically as a function of the slab thickness and the external magnetic field for several III-V and II-VI compounds. It is found that the renormalized cyclotron frequency increases with increasing slab thickness and with increasing magnetic field. The contributions of the bulk-optical phonons and the surface-optical phonons for the renormalization of the cyclotron frequency are also discussed.

• Received 3 November 1987

DOI:https://doi.org/10.1103/PhysRevB.38.3459