Dimer-Quadrupolar Quantum Phase Transition in the Quasi-One-Dimensional Heisenberg Model with Biquadratic Interaction

TL;DR

This study uses quantum Monte Carlo simulations to explore phase transitions in a quasi-one-dimensional S=1 Heisenberg antiferromagnet with biquadratic interactions, revealing a transition from a dimerized phase to Nél ordered or spin nematic phases.

Contribution

It provides new insights into the nature of quantum phase transitions involving dimerization and quadrupolar order in low-dimensional spin systems.

Findings

Identification of a phase transition driven by inter-chain coupling

Evidence for an unconventional second-order transition

Observation of a transition from dimerized to Nél or spin nematic phases

Abstract

The quasi-one-dimensional S=1 Heisenberg antiferromagnet with a biquadratic term is investigated at zero temperature by quantum Monte Carlo simulation. As the magnitude of the inter-chain coupling is increased, the system undergoes a phase transition from a spontaneously dimerized phase to a N\'eel ordered or spin nematic phase. The numerical results suggest the possibility of an unconventional second-order transition in which the symmetry group characterizing one phase is not a subgroup of the other.