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Metamagnetism of antiferromagnetic XXZ quantum spin chains

Toru Sakai·Minoru Takahashi
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Abstract

The magnetization process of the one-dimensional antiferromagnetic Heisenberg model with the Ising-like anisotropic exchange interaction is studied by the exact diagonalization technique. It results in the evidence of the first-order spin flop transition with a finite magnetization jump in the Néel ordered phase for $S\geq 1$. It implies that the S=1/2 chain is an exceptional case where the metamagnetic transition becomes second-order due to large quantum fluctuations.

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Toru Sakai, Minoru Takahashi. 1999-03-27. Metamagnetism of antiferromagnetic XXZ quantum spin chains. https://doi.org/10.1103/physrevb.60.7295

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