Low temperature absorption edge and photoluminescence study in TlIn(Se1−xSx)2 layered mixed crystals

Photoluminescence spectra of TlIn(Se1−xSx)2 mixed crystals were studied in the wavelength region of 400-620 nm at T = 10 K. The observed bands were attributed to the transitions of electrons from shallow donor levels to the valence band. The shift of the PL bands to higher energies with elevating sulfur content was revealed. Moreover, the composition ratio of the mixed crystals was obtained from the energy dispersive spectroscopy measurements.