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arXiv:cond-mat/0201518 · Physical review. B, Condensed matter

Frustration-induced phase transitions in the spin- S orthogonal-dimer chain

Akihisa Koga, Norio Kawakami

Published May 30, 2002• 21 citations
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Abstract

We investigate quantum phase transitions in a frustrated orthogonal-dimer chain with an arbitrary spin $S>~1/2.$ When the ratio of the competing exchange couplings is varied, first-order phase transitions occur $2S$ times among distinct spin-gap phases. The introduction of single-ion anisotropy further enriches the phase diagram. The phase transitions described by the present model possess most of the essential properties inherent in frustrated quantum spin systems.

DOI
10.1103/physrevb.65.214415

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