Spin glass behavior of Zn_1-xMn_xTe

We have performed ac susceptibility and dc magnetization measurements on the diluted magnetic semiconductor Zn_1-xMn_xTe. The measurements clearly indicate spin glass behavior. For an x=0.4 sample, the data for the imaginary part of the complex susceptibility (X″) was analyzed according to conventional power-law dynamics and good scaling was obtained with T_c=13.4±0.2 K, z υ = 10.5 ± 1.0, and β=0.9±0.2. These values of z υ and β are consistent with results obtained in other spin glass systems. The scaling of the X″ data was not as good when analyzed within the activated dynamics model. Magnetization measurements of an x=0.5 sample also showed a spin glass-like transition. Scaling of the nonlinear magnetization just above the transition gave T_c = 20.8 ± 0.2 K, and the critical exponent values β=0.8±0.2 and γ=4.0±1.0. This confirms the β value obtained from the ac measurements and the γ value is in fair agreement with reported values for other diluted magnetic semiconductor spin glass systems. We conclude that Zn_1-xMn_xTe and similar systems undergo equilibrium phase transitions to a spin glass state at low temperatures.