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arXiv · 1901.01514

Surface energy and elementary excitations of the XXZ spin chain with arbitrary boundary fields

Pei Sun·Zhi-Rong Xin·Yi Qiao·Kun Hao·Like Cao·Junpeng Cao·Tao Yang·Wen-Li Yang
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Abstract

The thermodynamic properties of the XXZ spin chain with integrable open boundary conditions at the gaped region (i.e., the anisotropic parameter $\eta$ being a real number) are investigated.It is shown that the contribution of the inhomogeneous term in the $T-Q$ relation of the ground state and elementary excited state can be neglected when the size of the system $N$ tends to infinity. The surface energy and elementary excitations induced by the unparallel boundary magnetic fields are obtained.

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Pei Sun, Zhi-Rong Xin, Yi Qiao, Kun Hao, Like Cao, Junpeng Cao, Tao Yang, Wen-Li Yang. 2019-01-06. Surface energy and elementary excitations of the XXZ spin chain with arbitrary boundary fields. https://doi.org/10.1088/1751-8121/ab2259

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