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Re-Entrant Quantum Phase Transitions in Antiferromagnetic Spin-1 Ladders

Shoji Yamamoto·Toru Sakai·Akihisa Koga
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Abstract

In response to recent chemical attempts to construct higher-spin ladder materials from organic polyradicals, we study the ground-state properties of a wide class of antiferromagnetic spin-1 ladders. Employing various numerical tools, we reveal the rich phase diagram and correct a preceding nonlinear-sigma-model prediction. A variational analysis well interprets the phase competition with particular emphasis on the {\it re-entrant phase boundary} as a function of the rung interaction.

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Shoji Yamamoto, Toru Sakai, Akihisa Koga. 2002-06-27. Re-Entrant Quantum Phase Transitions in Antiferromagnetic Spin-1 Ladders. https://doi.org/10.1143/jpsj.71.1250

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