Metamagnetism collective electron

Three types of characteristic behaviours are mainly observed for R concentrations near or larger than the critical ones, namely collective electron metamagnetism (CEM), very weak itinerant ferromagnetism (VWIF) and Co antiferromagnetism. 

Fig. 2. Collective Electron Metamagnetism, (a) Variation of the difference between the ftee energy of the ferromagnetic and paramagnetic states as a function of magnetization at different fields (b) variation of magnetization with increasing field (Barbara et al. 1988).

Fig. 3. Schematic representation of the Collective Electron Metamagnetism, (a) M vs. H at various temperatures (b) thermal variation of the initial susceptibility (Gignoux et al. 1983).

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