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arXiv · 1409.7070

Quantum Selection of Order in an $XXZ$ Antiferromagnet on a Kagomé Lattice

A. L. Chernyshev·M. E. Zhitomirsky
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Abstract

Selection of the ground state of the kagomé-lattice $XXZ$ antiferromagnet by quantum fluctuations is investigated by combining non-linear spin-wave and real-space perturbation theories. The two methods unanimously favor ${\bf q}=0$ over $\sqrt{3}\times\sqrt{3}$ magnetic order in a wide range of the anisotropy parameter $0\leq Δ\leq 0.72$. Both approaches are also in an accord on the magnitude of the quantum order-by-disorder effect generated by topologically non-trivial, loop-like spin-flip processes. A tentative $S-Δ$ phase diagram of the model is proposed.

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A. L. Chernyshev, M. E. Zhitomirsky. 2014-11-08. Quantum Selection of Order in an $XXZ$ Antiferromagnet on a Kagomé Lattice. https://doi.org/10.1103/physrevlett.113.237202

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