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arXiv · hep-th/9411112

XXZ chain with a boundary

M. Jimbo·R. Kedem·T. Kojima·H. Konno·T. Miwa
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Abstract

The $\XXZ$ spin chain with a boundary magnetic field $h$ is considered, using the vertex operator approach to diagonalize the Hamiltonian. We find explicit bosonic formulas for the two vacuum vectors with zero particle content. There are three distinct regions when $h\geq0$, in which the structure of the vacuum states is different. Excited states are given by the action of vertex operators on the vacuum states. We derive the boundary $S$-matrix and present an integral formula for the correlation functions. The boundary magnetization exhibits boundary hysteresis. We also discuss the rational limit, the $\XXX$ model.

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M. Jimbo, R. Kedem, T. Kojima, H. Konno, T. Miwa. 1994-12-01. XXZ chain with a boundary. https://doi.org/10.1016/0550-3213(95)00062-w

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