Nickel impurity excitons and photoinduced lattice distortion in ZnSe1−y Sy:Ni and Zn1−x CdxSe:Ni solid solutions

Abstract

A heavy dependence of the zero-phonon line of the donor Ni excitons and of a series of its phonon replicas on the composition of ZnSe1−ySy:Ni and Zn1−xCdxSe:Ni solid solutions was studied. A model of nonradiative recombination of impurity excitons with allowance made for an intermediate virtual state {d8} is discussed in detail. It is shown that this state depends on the lattice distortion induced by the Ni3+ impurity center whose charge is positive in reference to the lattice.