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

Akihisa Koga·Norio Kawakami
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Abstract

We investigate quantum phase transitions in the frustrated orthogonal-dimer chain with an arbitrary spin $S \geq 1/2$. 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.

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Akihisa Koga, Norio Kawakami. 2002-01-28. Frustration-induced phase transitions in the spin-S orthogonal-dimer chain. https://doi.org/10.1103/physrevb.65.214415

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