Spin Glass Behaviour

AuFe like CuMn is one of the well known prototype systems showing magnetic spin glass behaviour at low temperatures. It may be recognized that by the above method we are... 

R. Clad, R. Kuentzler and W. Pfeiler, Atomic short-range order and spin-glass behaviour in concentrated... 

The Schottky-like anomaly observed in the specific heat of the compounds discussed in this section can be derived phenomenologically using (a) the resonance-level model, (b) the spin glass behaviour, (c) the crystal field (Schottky) contribution or even (d) low-dimensional magnetic fluctuations. The cases where an HF behaviour is deduced from a large value will be discussed in sect. 9, in connection with the contribution to of the excited crystal field levels. It is clear that complementary techniques, such as NMR, AC susceptibility and electrical resistivity, can easily reveal the magnetic character of the microscopic interactions. In some of the HF compounds the ratio between the y term and the (( -> 0) = Xo value of the susceptibility, and between the / term and the coefficient of the resistivity. A, have values predicted by... 

On the other hand Hilscher et al. (1977) found by recent pressure experiments that dTcIdp is zero around the critical concentration 0.3Stoner-Wohlfarth theory does not apply simply, and the magnetic break down cannot be correlated with a minimum of the density of states curve. 

The compound PrP exists off-stoichiometry, as found by Franceschi and Olcese (1968), with the NaCl structure. Phosphor-deficient samples show an induced magnetic moment on the Pr sites (Hasanain et al. 1981). Spin-glass behaviour (Westerholt and Methfessel 1977) seems to occur in such compounds. 

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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