SPIN-GLASS BEHAVIOR OF ZN1-XMNXTE

We have performed ac susceptibility and de magnetization measurements on the diluted magnetic semiconductor Zn1-xMnxTe. The measurements cle arly indicate spin glass behavior. For an x = 0.4 sample, the data for the imaginary part of the complex susceptibility (chi'') was analyzed according to conventional power-law dynamics and good scaling was obt ained with T-c = 13.4 +/- 0.2 K, zv = 10.5 +/- 1.0, and beta = 0.9 +/- 0.2. These values of zv and beta are consistent with results obtained in other spin glass systems. The scaling of the chi'' 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 trans ition, Scaling of the nonlinear magnetization just above the transitio n gave T-c = 20.8 +/- 0.2 K, and the critical exponent values beta = 0 .8 +/- 0.2 and gamma = 4.0 +/- 1.0. This confirms the beta value obtai ned from the ac measurements and the gamma value is in fair agreement with reported values for other diluted magnetic semiconductor spin gla ss systems. We conclude that Zn1-xMnxTe and similar systems undergo eq uilibrium phase transitions to a spin glass state at low temperatures. (C) 1996 American institute of Physics.