Absorption Spectrum of Nickel in Gallium Phosphide

Abstract

Optical absorption due to transitions within the $d$ shell of $\mathrm{Ni}\left(d^8\right)$ as an impurity in GaP has been observed and interpreted. The crystal-field parameters deduced are $B=310\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, $\Delta =5500\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$. An apparent reduction of the first-order spin-orbit interaction in the ${}_{}{}^3{}_{}{}^{}T_1^{}{}_{}{}^{}\mathrm{}\left(P\right)\mathrm{}$ state is taken to be a manifestation of the Ham effect.