Spin-Flip Energy Transfer from Photocarriers to Magnetic Ions in (Cd,Mn)Te

Abstract

The process of energy exchange from photoinjected carriers to magnetic ions is studied by means of polarization-dependent magnetophotoluminescence in Cd 1Àx Mn x Te (x Mn ¼ 0:1). It is observed for the first time that the photothermalization of magnetic ions depends on the initial spin state of carriers, prepared by circularly polarized excitation, revealing the contribution of the spin flip-flop process to the energy transfer. Suppression of heat accumulation, exploiting low-repetition pulsed excitation, enables us to temporally resolve the spin exchange process associated with a single scattering event. Our results suggest the presence of spatial distribution in magnetization as a result of rapid carrier localization.