Integrable Kondo impurities in the one-dimensional supersymmetric U model of strongly correlated electrons

TL;DR

This paper investigates integrable Kondo impurities within a one-dimensional supersymmetric U model, deriving boundary matrices, diagonalizing the Hamiltonian, and revealing unique boundary parameter properties in strongly correlated electron systems.

Contribution

It introduces a novel integrable impurity model with boundary K matrices dependent on local magnetic moments, and derives the Bethe ansatz equations for this system.

Findings

Model exhibits a free parameter in the bulk Hamiltonian

No free boundary parameters, contrasting with other models

Bethe ansatz equations derived for the system

Abstract

Integrable Kondo impurities in the one-dimensional supersymmetric U model of strongly correlated electrons are studied by means of the boundary graded quantum inverse scattering method. The boundary K matrices depending on the local magnetic moments of the impurities are presented as nontrivial realizations of the reflection equation algebras in an impurity Hilbert space. Furthermore, the model Hamiltonian is diagonalized and the Bethe ansatz equations are derived. It is interesting to note that our model exhibits a free parameter in the bulk Hamiltonian but no free parameter exists on the boundaries. This is in sharp contrast to the impurity models arising from the supersymmetric t-J and extended Hubbard models where there is no free parameter in the bulk but there is a free parameter on each boundary.