Quantum spin nematics, dimerization, and deconfined criticality in quasi-one dimensional spin-1 magnets

TL;DR

This paper develops a theoretical framework for understanding how quantum fluctuations destroy spin nematic order in quasi-one dimensional spin-1 magnets, leading to dimerization and a novel second-order phase transition.

Contribution

It introduces a Landau-forbidden second order transition theory between spin nematic and dimerized states, supported by numerical calculations and predictions.

Findings

Quantum fluctuations induce dimerization in disordered nematic states.

A Landau-forbidden second order transition is proposed.

Numerical tests are suggested to validate the theory.

Abstract

We study theoretically the destruction of spin nematic order due to quantum fluctuations in quasi-one dimensional spin-1 magnets. If the nematic ordering is disordered by condensing disclinations then quantum Berry phase effects induce dimerization in the resulting paramagnet. We develop a theory for a Landau-forbidden second order transition between the spin nematic and dimerized states found in recent numerical calculations. Numerical tests of the theory are suggested.