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Theory of the metamagnetic crossover in CeRu_2Si_2

Hiroyuki Satoh·Fusayoshi J. Ohkawa
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Abstract

Based on the periodic Anderson model, it is shown that the competition between the quenching of magnetic moments by local quantum spin fluctuations and a magnetic exchange interaction caused by the virtual exchange of pair excitations of quasiparticles in spin channels is responsible for the metamagnetic crossover in CeRu_2Si_2, cooperated with the electron-lattice interaction. The strength of the exchange interaction is proportional to the bandwidth of quasiparticles and its sign changes with increasing magnetizations; it is antiferromagnetic in the absence of magnetizations, whereas it is ferromagnetic in the metamagnetic crossover region. Experimental results of static quantities are well reproduced.

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Hiroyuki Satoh, Fusayoshi J. Ohkawa. 2000-11-08. Theory of the metamagnetic crossover in CeRu_2Si_2. https://doi.org/10.1016/s0921-4526(99)00956-4

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