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Field induced transition of the S=1 antiferromagnetic chain with anisotropy

Toru Sakai
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Abstract

The ground state magnetization process of the S=1 antiferromagnetic chain with the easy-axis single-ion anisotropy described by negative $D$ is investigated. It is numerically found that a phase transition between two different gapless phases occurs at an intermediate magnetic field between the starting and saturation points of the magnetization for $-1.49<D<-0.35$. The transition is similar to the spin flopping, but it is second-order and not accompanied with any significant anomalous behaviors in the magnetization curve. We also present the phase diagrams in the m-D and H-D planes which reveal a possible re-entrant transition.

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Toru Sakai. 1998-06-17. Field induced transition of the S=1 antiferromagnetic chain with anisotropy. https://doi.org/10.1103/physrevb.58.6268

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