Spin glass behavior of Zn1−xMnxTe

Abstract

We have performed ac susceptibility and dc magnetization measurements on the diluted magnetic semiconductor Zn1−xMnxTe. The measurements clearly indicate spin glass behavior. For an x=0.4 sample, the data for the imaginary part of the complex susceptibility (χ″) was analyzed according to conventional power-law dynamics and good scaling was obtained with Tc=13.4±0.2 K, zν=10.5±1.0, and β=0.9±0.2. These values of zν and β are consistent with results obtained in other spin glass systems. The scaling of the χ″ 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 Tc=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 Zn1−xMnxTe and similar systems undergo equilibrium phase transitions to a spin glass state at low temperatures.