Large Lattice Distortion Induced by Mn²⁺ Excitation in Cd_1−xMn_xTe

抄録

Photoluminescence spectra of Mn²⁺-related transition assigned as ⁴T₁–⁶A₁ in Cd_1−xMn_xTe (x=0.4 to 0.7) are investigated in a temperature range from 10 K to 220 K and under hydrostatic pressures up to 20 kbar. The observed temperature dependence of the spectral width shows that in the low-temperature region (10 K to 80 K) a configuration coordinate model is adopted, but in the high-temperature region, using the model, there is deviation from the calculated results. We consider that the equilibrium position Q₀ in the excited states changes toward that in the ground state increasing temperature above 80 K. In addition, anomalous behavior in the temperature dependence of the pressure coefficient of the luminescence peak energy is observed at about 80 K, which is related to the change of Q₀.