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arXiv:cond-mat/0412234 · Journal of the Physical Society of Japan

Finite-Field Ground State of theS=1 Antiferromagnetic–Ferromagnetic Bond-Alternating Chain

Takashi Tonegawa, Kiyomi Okamoto, Makoto Kaburagi

Published Jan 1, 2005• 1 citation
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Abstract

We investigate the finite-field ground state of the S=1 antiferromagnetic-ferromagnetic bond-alternating chain described by the Hamiltonian ${\calH}=\sum\nolimits_{\ell}\bigl\{\vecS_{2\ell-1}\cdot\vecS_{2\ell} +J\vecS_{2\ell}\cdot\vecS_{2\ell+1}\bigr\} +D\sum\nolimits_{\ell} \bigl(S_{\ell}^z)^2 -H\textstyle\sum\nolimits_\ell S_\ell^z$, where \hbox{$J\leq0$} and \hbox{$-\infty

DOI
10.1143/jpsjs.74s.161

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