Quantitative Analysis of Interference Structures in the Transmission Spectrum of Very Thin CdS Platelets

Abstract
A quantitative analysis is given of interference structures appearing in very thin CdS single crystals of high perfection at 1.8K on both sides of the A ground‐state exciton. It is shown that the structures are due to Fabry‐Perot interferences of polaritons of the lower and upper branch, respectively. From the analysis of the interferences the energy of the transversal exciton is determined with high precision to be Et = 2.5528 eV, shifted from the transmission minimum by 0.8 meV in the low energy direction. This is to be expected in the polariton model.