Temperature and excitation intensity tuned photoluminescence in Ga0.75In0.25Se crystals

Abstract Photoluminescence (PL) spectra of Ga0.75In0.25Se layered single crystals have been studied in the wavelength range of 580–670 nm and temperature range of 7–59 K. Two PL emission bands centered at 613 nm (2.02 eV, A-band) and 623 nm (1.99 eV, B-band) were revealed at T = 7 K. The excitation laser intensity dependence of the emission bands have been studied in the 0.06–1.40 W cm−2 range. Radiative transitions from shallow donor levels located at EA = 0.11 and EB = 0.15 eV below the bottom of conduction band to single shallow acceptor level located at 0.01 eV above the valence band are suggested to be responsible for the observed A- and B-bands. A simple model was proposed to interpret the recombination processes in Ga0.75In0.25Se single crystals.