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Integrable Magnetic Model of Two Chains Coupled by Four-Body Interactions

Norihiro Muramoto·Minoru Takahashi
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Abstract

An exact solution for an XXZ chain with four-body interactions is obtained and its phase diagram is determined. The model can be reduced to two chains coupled by four-body interactions, and it is shown that the ground state of the two-chain model is magnetized in part. Furthermore, a twisted four-body correlation function of the anti-ferromagnetic Heisenberg chain is obtained.

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Norihiro Muramoto, Minoru Takahashi. 1999-03-12. Integrable Magnetic Model of Two Chains Coupled by Four-Body Interactions. https://doi.org/10.1143/jpsj.68.2098

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