1208.4306 (Kenji Harada)

Incommensurability of spiral state on the spin-1/2 spatially anisotropic
triangular antiferromagnets by using entanglement renormalization technique    [PDF]

Kenji Harada

We numerically study the ground state on the S=1/2 antiferromagnetic Heisenberg model on the spatially anisotropic triangular lattice, which is the effective model of Mott insulators on the triangular layer such as the organic charge transfer salts and Cs2CuCl4. We apply a numerical variational method by the tensor network with the entanglement renormalization, which improves the capability of describing a quantum state. We identify magnetic ground states for 0.7 <= J2/J1 <= 1 in the thermodynamic limit, where J1 and J2 denote the inner-chain and inter-chain coupling constants, respectively. Except for the isotropic case (J1=J2), the magnetic structure is spiral with the incommensurate wave vector that is different from the classical one. The quantum fluctuation weakens the effective coupling between chains, but the magnetic order remains in the thermodynamic limit. In addition, the incommensurate wave number is in good agreement with that of series expansion method.

View original: http://arxiv.org/abs/1208.4306