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Asymmetric Bethe Ansatz

Mathematical Physics 2024-10-02 v4 Quantum Gases math.MP Quantum Physics

Abstract

The recently proposed exact quantum solution for two δ\delta-function-interacting particles with a mass-ratio 3 ⁣: ⁣13\!:\!1 in a hard-wall box [Y. Liu, F. Qi, Y. Zhang and S. Chen, iScience 22, 181 (2019)] violates the conventional necessary condition for a Bethe Ansatz integrability, the condition being that the system must be reducible to a superposition of semi-transparent mirrors that is invariant under all the reflections it generates. In this article, we found a way to relax this condition: some of the semi-transparent mirrors of a known self-invariant mirror superposition can be replaced by the perfectly reflecting ones, thus breaking the self-invariance. The proposed name for the method is \emph{Asymmetric Bethe Ansatz} (Asymmetric BA). As a worked example, we study in detail the bound states of the nominally non-integrable system comprised of a bosonic dimer in a δ\delta-well. Finally, we show that the exact solution of the Liu-Qi-Zhang-Chen problem is a particular instance of the the Asymmetric BA.

Keywords

Cite

@article{arxiv.2311.15155,
  title  = {Asymmetric Bethe Ansatz},
  author = {Steven G. Jackson and Hélène Perrin and Gregory E. Astrakharchik and Maxim Olshanii},
  journal= {arXiv preprint arXiv:2311.15155},
  year   = {2024}
}
R2 v1 2026-06-28T13:31:34.248Z