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Spin Glass Ordering in Diluted Magnetic Semiconductors: a Monte Carlo Study

E. Marinari·V. Martín-Mayor·A. Pagnani
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Abstract

We study the temperature-dilution phase diagram of a site-diluted Heisenberg antiferromagnet on a fcc lattice, with and without the Dzyaloshinskii-Moriya anisotropic term, fixed to realistic microscopic parameters for $IIB_{1-x} Mn_x Te$ (IIB=Cd, Hg, Zn). We show that the dipolar Dzyaloshinskii-Moriya anisotropy induces a finite-temperature phase transition to a spin glass phase, at dilutions larger than 80%. The resulting probability distribution of the order parameter P(q) is similar to the one found in the cubic lattice Edwards-Anderson Ising model. The critical exponents undergo large finite size corrections, but tend to values similar to the ones of the Edwards-Anderson-Ising model.

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E. Marinari, V. Martín-Mayor, A. Pagnani. 2000-02-25. Spin Glass Ordering in Diluted Magnetic Semiconductors: a Monte Carlo Study. https://doi.org/10.1103/physrevb.62.4999

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