Realization of a spin liquid in a two dimensional quantum antiferromagnet

Abstract

The ground state properties of the two dimensional spatially anisotropic Heisenberg model are investigated by use of field theory mappings, spin-wave expansion, and Lanczos technique. Evidence for a disorder transition induced by anisotropy at about ${\mathit{J}}_{\mathit{y}}$/${\mathit{J}}_{\mathit{x}}$<0.1 is shown. We argue that the disordered phase is gapless and its long wavelength properties can be interpreted in terms of decoupled one dimensional chains.