Some optoelectronic properties of FeGaInSe4 crystals under laser excitation

Photoconductivity and photoluminescence of layered FeGaInSe4 crystals at high levels of optical excitation have been studied. It has been found out that decrease in the lifetime at high excitation intensities is due to the high concentration of non-equilibrium charge carriers generated by high-power laser radiation. The linear nature of the lux-ampere characteristic of photoconductivity is due to the transition of carriers from the valence band to the conduction band when FeGaInSe4 crystals are excited by the second harmonic of a neodymium laser. The photoluminescence band may be associated with a transition from the conduction band to the valence band or with a radiative transition from the trap levels below the bottom of the conduction band to the valence band.