Photo-Induced Paramagnetic Resonance of Chromium in Zinc Sulfide Crystals

Abstract
The optical excitation, stimulation, and quenching spectra of the paramagnetic resonance of 3d5 substitutional chromium in zinc sulfide single crystals have been measured. From these data the energy of the ground state of the chromium acceptor is estimated both when unoccupied and when occupied by a positive hole. In addition, the energies of gallium donors and copper acceptors have been verified by photo-ionization of these impurities in ZnS:Cr, Cu, Ga crystals, followed by capture of the carriers by the chromium, which is measured by the changes in the paramagnetic resonance. Finally, the characteristics of gallium-chromium pairs are considered.