English

$su(2)$ symmetry of XX spin chains

Statistical Mechanics 2025-12-25 v3 Mathematical Physics math.MP

Abstract

We show that, after suitably adjusting a uniform transverse magnetic field, the generic inhomogeneous open XX spin chain has a two-fold degeneracy, and an exact su(2)su(2) symmetry whose "inhomogeneous" nonlocal generators depend on coefficients that can be explicitly computed for models associated with discrete orthogonal polynomials.

Keywords

Cite

@article{arxiv.2508.20184,
  title  = {$su(2)$ symmetry of XX spin chains},
  author = {Nicolas Crampé and Rafael I. Nepomechie and Luc Vinet and Nabi Zare Harofteh},
  journal= {arXiv preprint arXiv:2508.20184},
  year   = {2025}
}

Comments

7 pages; v2: references added; v3: more references added