English

Strong-randomness infinite-coupling phase in a random quantum spin chain

Strongly Correlated Electrons 2014-01-14 v2 Disordered Systems and Neural Networks

Abstract

We study the ground-state phase diagram of the Ashkin-Teller random quantum spin chain by means of a generalization of the strong-disorder renormalization group. In addition to the conventional paramagnetic and ferromagnetic (Baxter) phases, we find a partially ordered phase characterized by strong randomness and infinite coupling between the colors. This unusual phase acts, at the same time, as a Griffiths phase for two distinct quantum phase transitions both of which are of infinite-randomness type. We also investigate the quantum multi-critical point that separates the two-phase and three-phase regions; and we discuss generalizations of our results to higher dimensions and other systems.

Keywords

Cite

@article{arxiv.1310.4864,
  title  = {Strong-randomness infinite-coupling phase in a random quantum spin chain},
  author = {Fawaz Hrahsheh and Rajesh Narayanan and José A. Hoyos and Thomas Vojta},
  journal= {arXiv preprint arXiv:1310.4864},
  year   = {2014}
}

Comments

9 pages, 6 eps figures, final version as published

R2 v1 2026-06-22T01:49:16.366Z