Relaxation dynamics of Mn2+ intraion excitation in Cd0.5Mn0.5Te: Dependence on the optical pumping level

A study is reported of the Mn2+ intracenter 3d luminescence in a dilute Cd0 .5Mn0.5Te magnetic semiconductor at pulsed excitations of up to 3.5 MW/cm(2 ). At high excitation levels and at a temperature of 77 K, the kinetics var ies strongly over the emission band profile. The luminescence decay curve c an be resolved into a fast and a delayed component, which correspond to the excitation of extended and localized states in the manganese ion system. T he fast relaxation of the extended states is largely determined by the up-c onversion. As the temperature is lowered, the contribution of the fast comp onent at the center of the emission band and in its low-energy wing decreas es because of the weakening role of the extended states lying above the mob ility edge. (C) 2001 MAIK "Nauka/Interperiodica".