Excitation and temperature tuned photoluminescence in HgGa2S4 single crystals Original Research Article

Mercury thiogallate single crystals are shown to exhibit bright photoluminescence (PL) tunable in a wide spectral range from green to red when changing the excitation power density, wavelength and sample temperature. Taking into account the excitation and temperature dependencies of the PL characteristics, a model accounting for the radiative electron transitions in HgGa2S4 is proposed. The values of the energy gap extrapolated to 0 K and of the linear and quadratic temperature coefficients of the energy gap were deduced from PL excitation experiments.