Nonlinear magnetization behavior near the spin-glass transition in the layered III-VI diluted magnetic semiconductor Ga 1 − x Mn x S

Magnetic properties of single crystalline Ga 1 − x Mn x S ( x = 0.09 ) have been measured near the spin-glass transition. No other III-VI DMS is currently known to exhibit a spin-glass transition for comparison with Ga 1 − x Mn x S . Ga 1 − x Mn x S ( T c = 11.2 K ) shows unexpected similarity to II-VI DMS Zn 1 − x Mn x Te ( T c = 20.8 K ) . For both systems, the quantity χ nl = − M nl ∕ H (where M nl = M total − M linear ) diverges as the temperature approaches the spin-glass transition temperature T c from above. It also increases with applied field at temperatures just above T c for both systems. The spin-glass transitions in both Ga 1 − x Mn x S and Zn 1 − x Mn x Te follow the same universal scaling function with the same critical exponent values ( γ = 4.0 ± 1.0 and β = 0.8 ± 0.2 ). The temperature of Ga 1 − x Mn x S 's low-field spin-glass transition cusp was found to occur at 10.9 K . As expected, this is slightly lower than the true spin-glass transition temperature T c = 11.2 ± 0.2 K obtained from the scaling analysis. The asymptotic, zero-field limit of the spin-glass transition cusp was found to persist at 10.9 K up to ∼ 1 T before being suppressed to lower temperatures with increasing field. Questions remain about if Ga 1 − x Mn x S should belong in the same universality class as Zn 1 − x Mn x Te since Ga 1 − x Mn x S is quasi-two-dimensional and Zn 1 − x Mn x Te is three-dimensional.