Near infrared luminescence of Ni and Fe doped ZnSe Crystals

A new photoluminescence band exhibiting fine structure with no-phonon line at 11178 cm-1 has been detected in ZnSe: Ni crystals. In view of the coincidence of this no-phonon line with the corressponding no-phonon absorption line this luminescence is interpreted as a3T1 (P)→3T1(F) transition at substitutional Ni2+ (3d8)ions in a tetrahedral crystal field. Coincidence between absorption and luminescence exists also between the corresponding no-phonon lines of the3T1(F)↔3T2(F) absorption and luminescence transitions indicating that T2 is the lowest level at the3T2(F) term. Iron doped ZnSe crystals show a fine structured luminescence band including two narrow no-phonon lines at 11154 cm-1 and 11128 cm-1. In accordance with similar experimental results using ZnS: Fe reported by Skowronski et al.[1] we interpret this luminescence as due to the3T1(H)→5E(D) transition within the Fe2+ion at tetrahedral site.