English

Quantum clock models with infinite-range interactions

Statistical Mechanics 2020-08-04 v3

Abstract

We study the phase diagram, both at zero and finite temperature, in a class of Zq\mathbb{Z}_q models with infinite range interactions. We are able to identify the transitions between a symmetry-breaking and a trivial phase by using a mean-field approach and a perturbative expansion. We perform our analysis on a Hamiltonian with 2p2p-body interactions and we find first-order transitions for any p>1p>1; in the case p=1p=1, the transitions are first-order for q=3q=3 and second-order otherwise. In the infinite-range case there is no trace of gapless incommensurate phase but, when the transverse field is maximally chiral, the model is in a symmetry-breaking phase for arbitrarily large fields. We analytically study the transtion in the limit of infinite qq, where the model possesses a continuous U(1)U(1) symmetry.

Keywords

Cite

@article{arxiv.2002.10494,
  title  = {Quantum clock models with infinite-range interactions},
  author = {Adu Offei-Danso and Federica Maria Surace and Fernando Iemini and Angelo Russomanno and Rosario Fazio},
  journal= {arXiv preprint arXiv:2002.10494},
  year   = {2020}
}
R2 v1 2026-06-23T13:52:14.237Z