English

Quantum Rotors on the AB$_2$ Chain with Competing Interactions

Strongly Correlated Electrons 2016-02-18 v1

Abstract

We present the ground state phase diagram of q=1/2q = 1/2 quantum-rotor chains with competing interactions (frustration) calculated through cluster variational mean field approaches. We consider two interaction patterns, named F1_1 and F2_2 models, between the quantum-rotor momentum and position operators, which follow exchange patterns of known one-dimensional spin-1/2 systems with a ferrimagnetic state in their phase diagrams. The spin-1/2 F1_1 model is known as the diamond chain and is related to the azurite compound, while the spin-1/2 F2_2 model was recently shown to present a frustration-induced condensation of magnons. We provide a detailed comparison between the quantum-rotor phase diagrams, in single- and multi-site mean-field approaches, and known results for the spin-1/2 models, including exact diagonalization and density matrix renormalization group data for these systems, as well as phase diagrams of the associated classical models.

Keywords

Cite

@article{arxiv.1602.05383,
  title  = {Quantum Rotors on the AB$_2$ Chain with Competing Interactions},
  author = {Antônio S. F. Tenório and R. R. Montenegro-Filho and M. D. Coutinho-Filho},
  journal= {arXiv preprint arXiv:1602.05383},
  year   = {2016}
}
R2 v1 2026-06-22T12:52:07.588Z