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arXiv · 0712.2269

Ordered Phases of the Anisotropic Kagome Lattice Antiferromagnet in a Field

E. M. Stoudenmire·Leon Balents
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Abstract

The antiferromagnetic Heisenberg model on an anisotropic kagome lattice may be a good minimal model for real magnetic systems as well as a limit from which the isotropic case can be better understood. We therefore study the nearest-neighbor Heisenberg antiferromagnet on an anisotropic kagome lattice in a magnetic field. Such a system should be well described by weakly interacting spin chains, and we motivate a general form for the interaction by symmetry considerations and by perturbatively projecting out the inter-chain spins. In the spin 1/2 case, we find that the system exhibits a quantum phase transition from a ferrimagnetic ordered state to an XY ordered state as the field is increased. Finally, we discuss the appearance of magnetization plateaux in the ferrimagnetic phase.

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E. M. Stoudenmire, Leon Balents. 2007-12-14. Ordered Phases of the Anisotropic Kagome Lattice Antiferromagnet in a Field. https://doi.org/10.1103/physrevb.77.174414

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