Electron spin dynamics in heavily Mn-doped (Ga,Mn)As

摘要

Electron spin relaxation and related mechanisms in heavily Mn-doped (Ga,Mn)As are studied by performing time-resolved magneto-optical Kerr effect measurements. At low temperature, s-d exchange scattering dominates electron spin relaxation, whereas the Bir-Aronov-Pikus mechanism and Mn impurity scattering play important roles at high temperature. The temperature-dependent spin relaxation time exhibits an anomaly around the Curie temperature (T_c) that implies that thermal fluctuation is suppressed by short-range correlated spin fluctuation above T_c.