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Phase Diagrams of S=3/2, 2 XXZ Spin Chains with Bond-Alternation

Atsuhiro Kitazawa·Kiyohide Nomura
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Abstract

We study the phase diagram of S=3/2 and S=2 bond-alternating spin chains numerically. In previous papers, the phase diagram of S=1 XXZ spin chain with bond-alternation was shown to reflect the hidden $Z_{2}\times Z_{2}$ symmetry. But for the higher S Heisenberg spin chain, the successive dimerization transition occurs, and for anisotropic spin chains the phase structure will be more colorful than the S=1 case. Using recently developed methods, we show directly that the phase structure of the anisotropic spin chains relates to the $Z_{2}\times Z_{2}$ symmetry.

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Atsuhiro Kitazawa, Kiyohide Nomura. 1997-05-26. Phase Diagrams of S=3/2, 2 XXZ Spin Chains with Bond-Alternation. https://doi.org/10.1143/jpsj.66.3379

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