Dynamics and transport of the Z_2 spin liquid: application to kappa-(ET)2Cu2(CN)3

TL;DR

This paper investigates the properties of Z_2 spin liquids in two dimensions, comparing theoretical predictions with experiments on kappa-(ET)2Cu2(CN)3, and suggests vison excitations significantly influence thermal transport.

Contribution

It provides a detailed analysis of Z_2 spin liquids' dynamics and transport, linking theoretical models to experimental observations in a specific organic compound.

Findings

Evidence of Z_2 spin liquid behavior in kappa-(ET)2Cu2(CN)3

Vison excitations dominate thermal transport properties

Thermal conductivity experiments reveal the vison gap

Abstract

We describe neutron scattering, NMR relaxation, and thermal transport properties of Z_2 spin liquids in two dimensions. Comparison to recent experiments on the spin S=1/2 triangular lattice antiferromagnet in kappa-(ET)2Cu2(CN)3 shows that this compound may realize a Z_2 spin liquid. We argue that the topological `vison' excitations dominate thermal transport, and that recent thermal conductivity experiments by M. Yamashita et al. have observed the vison gap.