1212.2286 (Natalia B. Perkins et al.)

Raman scattering in a Heisenberg S=1/2 antiferromagnet on the
anisotropic triangular lattice    [PDF]

Natalia B. Perkins, Gia-Wei Chern, Wolfram Brenig

We investigate the two-magnon Raman scattering from an anisotropic S=1/2 triangular Heisenberg antiferromagnet Cs2CuCl4. We find that the Raman response is very sensitive to magnon-magnon interactions and to scattering geometries, a feature that is in remarkable contrast with the polarization-independent Raman signal from the isotropic triangular Heisenberg antiferromagnet. Since a spin-liquid ground state gives rise to a similar rotationally invariant Raman response, our results on the polarization dependence of the scattering spectrum suggest that Raman spectroscopy provides a useful probe, complementary to neutron scattering, of the ground-state properties of Cs2CuCl4, particularly whether the time-reversal symmetry is broken in the ground state.

View original: http://arxiv.org/abs/1212.2286