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arXiv · 1504.00207

Small polaron with generic open boundary conditions revisit: exact solution via the off-diagonal Bethe ansatz

Xiaotian Xu·Junpeng Cao·Kun Hao·Zhan-Ying Yang·Wen-Li Yang
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Abstract

The small polaron, an one-dimensional lattice model of interacting spinless fermions, with generic non-diagonal boundary terms is studied by the off-diagonal Bethe ansatz method. The presence of the Grassmann valued non-diagonal boundary fields gives rise to a typical $U(1)$-symmetry-broken fermionic model. The exact spectra of the Hamiltonian and the associated Bethe ansatz equations are derived by constructing an inhomogeneous $T-Q$ relation.

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Xiaotian Xu, Junpeng Cao, Kun Hao, Zhan-Ying Yang, Wen-Li Yang. 2015-08-28. Small polaron with generic open boundary conditions revisit: exact solution via the off-diagonal Bethe ansatz. https://doi.org/10.1016/j.nuclphysb.2015.07.008

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