ABSTRACT

Optical properties of CaGa2S4 doped with Eu were investigated under low and high excitation power density. From the measured photoluminescence band shape, lifetime and quantum efficiency, maximum optical gain, corresponding to the case where all incorporated Eu ions (1 at %) are in the excited states, is estimated to be ∼50 cm−1 at the peak energy of emission band of 2.21 eV. A possibility of laser oscillation is proposed for a sample having a cavity of side pump geometry.