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Correlated-Electron Theory of Strongly Anisotropic Metamagnets

K. Held·M. Ulmke·D. Vollhardt
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Abstract

We present the first correlated-electron theory of metamagnetism in strongly anisotropic antiferromagnets. Quantum-Monte-Carlo techniques are used to calculate the field vs. temperature phase diagram of the infinite-dimensional Hubbard model with easy axis. A metamagnetic transition scenario with 1.~order and 2.~order phase transitions is found. The apparent similarities to the phase diagram of FeBr$_2$ and to mean-field results for the Ising model with competing interactions are discussed.

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K. Held, M. Ulmke, D. Vollhardt. 1995-05-29. Correlated-Electron Theory of Strongly Anisotropic Metamagnets. https://doi.org/10.1142/s0217984996000249

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