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arXiv · 1402.4008

A case study of spin-$1$ Heisenberg model in a triangular lattice

M. Moreno-Cardoner·H. Perrin·S. Paganelli·G. De Chiara·A. Sanpera
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Abstract

We study the spin-$1$ model in a triangular lattice in presence of a uniaxial anisotropy field using a Cluster Mean-Field approach (CMF). The interplay between antiferromagnetic exchange, lattice geometry and anisotropy forces Gutzwiller mean-field approaches to fail in a certain region of the phase diagram. There, the CMF yields two supersolid (SS) phases compatible with those present in the spin-$1/2$ XXZ model onto which the spin-$1$ system maps. Between these two SS phases, the three-sublattice order is broken and the results of the CMF depend heavily on the geometry and size of the cluster. We discuss the possible presence of a spin liquid in this region.

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M. Moreno-Cardoner, H. Perrin, S. Paganelli, G. De Chiara, A. Sanpera. 2014-02-17. A case study of spin-$1$ Heisenberg model in a triangular lattice. https://doi.org/10.1103/physrevb.90.144409

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