Heisenberg spin glasses

The pure RKKY interaction is isotropic, and the canonical spin glass systems are therefore often referred to as Heisenberg spin glasses. However, some anisotropy is also present in those systems originating from dipolar interaction and interaction of the Dzyaloshinsky-Moriya (DM) type [73]. The latter is due to spin-orbit scattering of the conduction electrons by non-magnetic impurities and reads... 

There are essential differences between the systems we have presented here, even in the limit of very strong anisotropy. The RKKY spin glasses are Heisenberg systems with random unidirectional anisotropy. Ferrofluids frozen under zero field are Heisenberg systems with random uniaxial anisotropy, while an Ising system is characterized by parallel uniaxial anisotropy. 

But surprisingly, Wendler et al. (1984) observe in the Heisenberg-Mke spin glass... 

Further experiments were done on the system CeSb-CeTe by Bartholin et al. (1985), Ravot and Achard (1982), Rossat-Mignod et al. (1982a, b), Escome et al. (1984) and Ravot et al. (1983). A 5% tellurium addition converts the highly anisotropic exchange observed in CeSb into the simple isotropic Heisenberg-type exchange. Sera et al. (1985) found in the system CeBi-CeTe a transition to spin-glass behaviour. 

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