Two-dimensional gapless spin liquids in frustrated SU(N) quantum magnets

TL;DR

This paper constructs frustrated SU(N) quantum magnet models, develops a mean field theory for spin liquids, and finds that their ground states are gapless with Dirac quasi-particles, offering insights into higher-dimensional spin liquid phases.

Contribution

It introduces a new class of frustrated SU(N) models and develops a mean field approach to analyze their gapless spin liquid states.

Findings

Ground states are gapless in two dimensions.

Quasi-particles behave as Dirac particles.

Potential relevance to higher-dimensional spin models.

Abstract

A class of the symmetrically frustrated SU(N) models is constructed for quantum magnets based on the generators of SU(N) group. The total Hamiltonian lacks SU(N) symmtry. A mean field theory in the quasi-particle representation is developed for spin liquid states. Numerical solutions in two dimension indicate that the ground states are gapless and the quasi-particles are Dirac particles. The mechanism may be helpful in exploring the spin liquid phases in the spin-1 bilinear-biquadratic model and the spin-orbital model in higher dimensions.