GaAs Polariton Interference in Magnetic Field: Oblique Incident Ellipsometry Measurement

Abstract

The properties of GaAs polaritons propagating in a magnetic field have been investigated using a self-designed ellipsometry system with an oblique incident angle. Interesting fine structures, which have not been reported, have been observed and their magneto-optical behavior cannot be explained by the known properties of excitonic states. Treating the surface and the growth interface as boundaries, we attribute the fine structures to the interference among various polariton modes. A model considering the polariton spatial dispersion and exciton effective mass increase induced by its center of mass and relative motion coupling is proposed to explain the magnetic response of interference ellipsometry spectra.