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arXiv · 1505.07943

Magnetization plateaus of an easy-axis Kagom\'e antiferromagnet with extended interactions

X. Plat·F. Alet·S. Capponi·K. Totsuka
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Abstract

We investigate the properties in finite magnetic field of an extended anisotropic XXZ spin-1/2 model on the Kagome lattice, originally introduced by Balents, Fisher, and Girvin [Phys. Rev. B, 65, 224412 (2002)]. The magnetization curve displays plateaus at magnetization m=1/6 and 1/3 when the anisotropy is large. Using low-energy effective constrained models (quantum loop and quantum dimer models), we discuss the nature of the plateau phases, found to be crystals that break discrete rotation and/or translation symmetries. Large-scale quantum Monte-Carlo simulations were carried out in particular for the m=1/6 plateau. We first map out the phase diagram of the effective quantum loop model with an additional loop-loop interaction to find stripe order around the point relevant for the original model as well as a topological Z2 spin liquid. The existence of a stripe crystalline phase is further evidenced by measuring both standard structure factor and entanglement entropy of the original microscopic model.

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X. Plat, F. Alet, S. Capponi, K. Totsuka. 2015-05-29. Magnetization plateaus of an easy-axis Kagom\'e antiferromagnet with extended interactions. https://doi.org/10.1103/physrevb.92.174402

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