Magneto-optical properties of Cd1−xMnxSe microcrystallites in SiO2 glass prepared by rf sputtering

Abstract

Cd_1−xMn_xSe microcrystallites have been successfully prepared by rf sputtering in SiO₂ matrix glass. Optical absorption edge shows high energy shifts of 20–550 meV to the high energy as compared to its position in bulk crystals; these shifts are interpreted as evidence for exciton confinement in the microcrystallites. Annealing of the Cd_1−xMn_xSe microcrystallites at 450–650 °C for 0.5–5 h increases the size of the microcrystallites from 20 to 250 Å. In an external magnetic field of 7 T the absorption edge shifts by 40 meV towards the low energy side due to the exchange coupling of the excitons with the d electrons of Mn²⁺ ions in the Cd_1−xMn_xSe microcrystallites. The spectral red shifts of the exciton luminescence in the Cd_1−xMn_xSe microcrystallites are also observed in the presence of magnetic fields. The corresponding effective g value varied from 138 at 1 T to 99 at 7 T.