Linear and Nonlinear Excitonic Absorption and Photoluminescence Spectra in Cu₂O: Line Shape Analysis and Exciton Drift

A complete analysis of the line shape of the excitonic absorption and photoluminescence lines of the yellow series of Cu₂O is given. A detailed fit to the absorption lines up to the n = 5 exciton according to Toyozawa's theory gives precise values for the excitonic resonance energies, allowing to calculate the excitonic Rydberg. The fit to the photoluminescence lines shows very good agreement with experimental data at different temperatures. At high excitation, the fit to the excitonic absorption lines reveals the fundamental mechanism for bleaching of exciton absorption lines in Cu₂O. Based on these findings, a new all-optical method for the observation of exciton transport in Cu₂O is proposed.