Drinfeld twists of the open XXZ chain with non-diagonal boundary terms

TL;DR

This paper constructs Drinfeld twists for the open XXZ spin chain with non-diagonal boundaries, leading to symmetric and polarization-free Bethe states in the F-basis, simplifying the analysis of the model.

Contribution

It introduces explicit Drinfeld twists for the open XXZ chain with non-diagonal boundary conditions, enabling symmetric Bethe state representations.

Findings

Bethe states expressed in a fully symmetric form

Pseudo-particle creation operators become polarization free in the F-basis

Explicit formulas for Bethe states are derived

Abstract

The Drinfeld twists or factorizing F-matrices for the open XXZ spin chain with non-diagonal boundary terms are constructed. It is shown that in the F-basis the two sets of pseudo-particle creation operators simultaneously take completely symmetric and polarization free form. The explicit and completely symmetric expressions of the two sets of Bethe states of the model are obtained.