Tower of states and the entanglement spectrum in a coplanar antiferromagnet

Abstract

I extend the analytical arguments of Metlitski and Grover (arXiv:1112.5166) to compute the entanglement spectrum and entanglement entropy of coplanar antiferromagnets with SO(3) order parameter symmetry. The low-energy states in the entanglement spectrum exhibit the tower-of-states structure, as is expected for systems that undergo spontaneous symmetry breaking. My results are consistent with numerical results on the triangular and Kagomé lattice.