Spin-glass ordering in the layered III-VI diluted magnetic semiconductor Ga1−xMnxS

Abstract

Magnetization and ac susceptibility measurements on single crystalline Ga1−xMnxS (x=0.09) have been measured near the spin-glass transition. No other III-VI diluted magnetic semiconductor (DMS) is currently known to exhibit a spin-glass transition for comparison with Ga1−xMnxS. Both the magnetization and ac susceptibility measurements were analyzed according to the appropriate universal scaling function for spin-glass transitions. The nonlinear magnetization scaled with the critical exponent values γ=4.0±1.0 and β=0.8±0.2 for a spin-glass transition temperature Tc=11.2±0.2 K. The analysis of the ac susceptibility’s out-of-phase component χ″(ω,T) yielded the parameter values Tc=10.8±0.3 K, zν=10±1, and β=0.6±0.3. The values of the critical exponents are consistent with those obtained in many DMS and non-DMS insulating spin glasses with different lattice structures and exchange interactions. These results indicate that III-V DMS materials such as Ga1−xMnxS belong in the same three-dimensional short-range Heisenberg universality class as other DMS and non-DMS insulating spin glasses.