Zero-Phonon Lines and Phonon Coupling of ZnSe: Mn and CdS: Mn

Absorption and emission spectra of ZnSe: Mn and of CdS: Mn crystals were measured at 4.2°K. The structure on the absorption and emission bands was identified in terms of phonon emission coupled to one electronic transition in each band. Zero-phonon lines were found in ZnSe: Mn at 18 025, 19 598, and 21 110 ${\mathrm{cm}}^{-1\mathrm{}}$ and in CdS: Mn at 18 620 ${\mathrm{cm}}^{-1\mathrm{}}$. They should correspond to the Mn transitions in a cubic crystalline field ${}_{}{}^6{}_{}{}^{}A_1^{}{}_{}{}^{}\to {}_{}{}^4{}_{}{}^{}T_1^{}{}_{}{}^{}$, ${}_{}{}^6{}_{}{}^{}A_1^{}{}_{}{}^{}\to {}_{}{}^4{}_{}{}^{}T_2^{}{}_{}{}^{}$, and ${}_{}{}^6{}_{}{}^{}A_1^{}{}_{}{}^{}\to {}_{}{}^4{}_{}{}^{}A_1^{}{}_{}{}^{}, {}_{}{}^4{}_{}{}^{}E$ in ZnSe. The ionic parameters $F_2=55\mathrm{}454$ and $F_4=34\mathrm{}520$ ${\mathrm{cm}}^{-1\mathrm{}}$ and the value of the crystalline field, $Dq=405\mathrm{}$ ${\mathrm{cm}}^{-1\mathrm{}}$, are deduced for Mn in ZnSe. Principal phonons participating have values of about 70, 94, 160, 209, and 242 ${\mathrm{cm}}^{-1\mathrm{}}$, which is in agreement with the phonon energies of the ZnSe host lattice.