Study of the impurity photoconductivity and luminescence in ZnSe:Ni crystals in the visible spectral region

The photoconductivity and photoluminescence spectra of ZnSe:Ni crystals in the visible spectral region are studied. It is established that the high-temperature impurity photoconductivity of ZnSe:Ni crystals is controlled by the optical transitions of electrons from the ground state $^3T_1(F)$ to high-energy excited states, with subsequent thermally activated transitions of electrons to the conduction band. A photoconductivity band associated with the photoionization of Ni impurities is revealed. The intracenter luminescence of ZnSe:Ni crystals is efficiently excited with light corresponding to the intrinsic absorption region of Ni$^{2+}$ ions.