Minima of the muon depolarization rate in Cd_1-xMn_xTe

Muon-spin rotation experiments were carried out on Cd_1-xMn_xTe samples with different Mn concentrations x and different annealing treatments (in Cd vapor or in vacuum). The purpose of the experiment was to elucidate the origin of the pronounced minima in the temperature dependence of the muon depolarization rate. We found that the data can be analyzed in a two-state model with the assumption that the muon has a high (10–30 μs^-1) depolarization rate in state one and a low (0.1–0.3 μs^-1) depolarization rate in state two. The minima are attributed to a change from state one (presumably a paramagnetic center) to state two (presumably a diamagnetic center). The state change is either purely electronic or caused by a site change of the muon.