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Integrable open-boundary conditions for the $q$-deformed supersymmetric $U$ model of strongly correlated electrons

Anthony J. Bracken·Xiang-Yu Ge·Yao-Zhong Zhang·Huan-Qiang Zhou
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Abstract

A general graded reflection equation algebra is proposed and the corresponding boundary quantum inverse scattering method is formulated. The formalism is applicable to all boundary lattice systems where an invertible R-matrix exists. As an application, the integrable open-boundary conditions for the $q$-deformed supersymmetric $U$ model of strongly correlated electrons are investigated. The diagonal boundary K-matrices are found and a class of integrable boundary terms are determined. The boundary system is solved by means of the coordinate space Bethe ansatz technique and the Bethe ansatz equations are derived. As a sideline, it is shown that all R-matrices associated with a quantum affine superalgebra enjoy the crossing-unitarity property.

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Anthony J. Bracken, Xiang-Yu Ge, Yao-Zhong Zhang, Huan-Qiang Zhou. 1998-01-18. Integrable open-boundary conditions for the $q$-deformed supersymmetric $U$ model of strongly correlated electrons. https://doi.org/10.1016/s0550-3213(98)00067-4

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