Condensation of anyons in frustrated quantum magnets

Phys Rev Lett. 2012 Nov 30;109(22):227203. doi: 10.1103/PhysRevLett.109.227203. Epub 2012 Nov 28.

Abstract

We derive the exact ground space of a family of spin-1/2 Heisenberg chains with uniaxial exchange anisotropy (XXZ) and interactions between nearest and next-nearest-neighbor spins. The Hamiltonian family, H(eff)(Q), is parametrized by a single variable Q. By using a generalized Jordan-Wigner transformation that maps spins into anyons, we show that the exact ground states of H(eff)(Q) correspond to a condensation of anyons with a statistical phase φ=-4Q. We also provide matrix-product state representations of some ground states that allow for the efficient computation of spin-spin correlation functions.