On the properties of cobalt impurities in zinc selenide crystals. I. Effect of in‐band position of states on photoelectric properties

The absorption and photoconductivity spectra of ZnSe:Co in the spectral region of the 4A2(4F) → → 4T1(4F) and 4A2(4F) → 4T1(4P) crystal field transitions within the 3d7 shell of the Co2+ ion are presented. The structure of the photocurrent observed here is associated with the degeneracy of the 4T1(4P) and 4T1(4F) excited states of the Co2+ ion with the conduction band of ZnSe. The autoionization times of Co2+ ion via those states to the conduction band are estimated to lie within the range of 10−9 to 10−4 s.