Algebraic Vortex Liquid in Spin-1/2 Triangular Antiferromagnets: Scenario for Cs2CuCl4
Motivated by inelastic neutron scattering data on Cs2CuCl4, we explore spin-1/2 triangular lattice antiferromagnets with both spatial and easy-plane exchange anisotropies, the latter due to an observed Dzyaloshinskii-Moriya interaction. Exploiting a duality mapping followed by a fermionization of the dual vortex degrees of freedom, we find a novel critical spin-liquid phase described in terms of Dirac fermions with an emergent global SU(4) symmetry minimally coupled to a noncompact U(1) gauge field. This "algebraic vortex liquid" supports gapless spin excitations and universal power-law correlations in the dynamical spin structure factor which are consistent with those observed in Cs2CuCl4. We suggest future neutron scattering experiments that should help distinguish between the algebraic vortex liquid and other spin liquids and quantum critical points previously proposed in the context of Cs2CuCl4.
Additional Information© 2005 The American Physical Society (Received 26 August 2005; published 6 December 2005) We would like to thank Leon Balents, T. Senthil, and Martin Veillette for sharing their insights, and especially Michael Hermele for an initial collaboration. This work was supported by the National Science Foundation (J.A.) through Grants No. PHY-9907949 (O.I.M. and M.P.A.F.) and No. DMR-0210790 (M.P.A.F.).
Published - ALIprl05.pdf