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arXiv · 1610.01523

How to fold a spin chain: Integrable boundaries of the Heisenberg XXX and Inozemtsev hyperbolic models

Alejandro De La Rosa Gomez·Niall MacKay·Vidas Regelskis
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Abstract

We present a general method of folding an integrable spin chain, defined on a line, to obtain an integrable open spin chain, defined on a half-line. We illustrate our method through two fundamental models with sl(2) Lie algebra symmetry: the Heisenberg XXX and the Inozemtsev hyperbolic spin chains. We obtain new long-range boundary Hamiltonians and demonstrate that they exhibit Yangian symmetries, thus ensuring integrability of the models we obtain. The method presented provides a "bottom-up" approach for constructing integrable boundaries and can be applied to any spin chain model.

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Alejandro De La Rosa Gomez, Niall MacKay, Vidas Regelskis. 2017-03-03. How to fold a spin chain: Integrable boundaries of the Heisenberg XXX and Inozemtsev hyperbolic models. https://doi.org/10.1016/j.physleta.2017.02.039

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