We propose a finite-temperature phase diagram for the 2D spin-1/2J1−J2XXZ antiferromagnet on the triangular lattice. Our analysis, based on a composite fermion representation, yields several phases. This includes a zero-temperature helical spin liquid with N=6 {\it anisotropic} Dirac cones, and with nonzero vector chirality implying a broken Z2 symmetry. It is terminated at T=0 by a continuous quantum phase transition to 120∘ ordered state around J2/J1≈0.089 in the XX limit; these phases share a double degeneracy, which persists to finite T above the helical spin liquid. By contrast, at J2/J1≃0.116, the transition into a stripe phase appears as first order. We further discuss experimental and numerical consequences of the helical order and the anisotropic nature of the Dirac dispersion.
@article{arxiv.1911.02932,
title = {Helical spin liquid in a triangular XXZ magnet from Chern-Simons theory},
author = {Tigran A. Sedrakyan and Roderich Moessner and Alex Kamenev},
journal= {arXiv preprint arXiv:1911.02932},
year = {2020}
}