Spatial dispersion in polariton spectra of CuGaS2 crystals

Abstract

TIn this study, we obtained new data on the parameters of the long-wavelength exciton polaritons of the A series and studied the wavelength-modulated reflectivity spectra of the A, B, and C excitons, the luminescence spectra, and the reflectivity and the luminescence spectra as functions of the angle of incidence of the exciting beam of CuGaS2 crystals in the range of the A exciton absorption at 77 and 8 K. We also obtained information on the parameters of excitons, their band structure, and anisotropy of the exciton mass.