Spin transport of the frustrated quasi-two-dimensional Heisenberg antiferromagnet

We use the Self Consistent Harmonic Approximation together with the Kubo formalism of the Linear Response Theory to study the spin transport in the quasi-two-dimensional frustrated Heisenberg antiferromagnet in a square lattice with easy-plane ion single anisotropy at zero temperature. The regular part of the spin conductivity $\sigma^{reg}(\omega)$ is determined for several values of the critical ion single parameter $D_{c}$, that separates the low $D$ region from the large $D$ quantum paramagnetic phase. We have obtained an abrupt change in the spin conductivity in the point of phase transition indicating a strong influence of frustration on the spin transport properties