A Gaudin-like determinant for overlaps of Néel and XXZ Bethe states
arXiv:1401.2877 · doi:10.1088/1751-8113/47/14/145003
Abstract
We derive a determinant expression for overlaps of Bethe states of the XXZ spin chain with the N{é}el state, the ground state of the system in the antiferromagnetic Ising limit. Our formula, of determinant form, is valid for generic system size. Interestingly, it is remarkably similar to the well-known Gaudin formula for the norm of Bethe states, and to another recently-derived overlap formula appearing in the Lieb-Liniger model.
10 pages