Interference of additional waves of excitonic polaritons in SnSe single crystals

Abstract

Absorption, reflection, photoluminescence, wavelength modulation reflection and transmission spectra at temperatures 300–10 K in energy rage 1.1–1.5 eV were investigated. Contours of excitonic reflection spectra were calculated and the binding energy (Rydberg constant), translation (M) and reduced (µ *) effective masses of excitons were determined. Effective masses of electrons and holes were estimated. In the region of A and B excitonic series sparse and thick interference fringes were observed in measured spectra. The sparse fringes are due to Fabry-Perot interference of excitonic polaritons of lower polaritonic branch (ωT). The thick interference is caused by the mutual interference of excitonic polaritons of lower (ωT) and upper (ωL) polaritonic branches