Abstract
The ground state of an antiferromagnetic Heisenberg model on a spatially anisotropic triangular lattice, which is an effective model of Mott insulators on a triangular layer of organic charge transfer salts or CsCuCl, is numerically studied. We apply a numerical variational method by using a tensor network with entanglement renormalization, which improves the capability of describing a quantum state. Magnetic ground states are identified for in the thermodynamic limit, where and denote the innerchain and interchain coupling constants, respectively. Except for the isotropic case (), the magnetic structure is spiral with an 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 the series expansion method.
7 More- Received 14 September 2012
DOI:https://doi.org/10.1103/PhysRevB.86.184421
©2012 American Physical Society