Boundary S matrices for the open Hubbard chain with boundary fields

TL;DR

This paper derives boundary S matrices for the open Hubbard chain with boundary fields, revealing how boundary conditions influence charge excitations while preserving spin symmetry, using a method from Grisaru et al.

Contribution

It applies Grisaru et al.'s method to compute boundary S matrices for the open Hubbard chain, highlighting the dependence on boundary fields without breaking spin symmetry.

Findings

Boundary S matrices depend on boundary fields for charge excitations.

Spin-SU(2) symmetry remains unbroken despite boundary fields.

The method contrasts with the open supersymmetric t-J model.

Abstract

Using the method introduced by Grisaru et al., boundary S matrices for the physical excitations of the open Hubbard chain with boundary fields are studied. In contrast to the open supersymmetric t-J model, the boundary S matrix for the charge excitations depend on the boundary fields though the boundary fields do not break the spin-SU(2) symmetry.