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arXiv · 1910.10448

Magnon crystallization in the kagome lattice antiferromagnet

J. Schnack·J. Schulenburg·A. Honecker·J. Richter
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Abstract

We present numerical evidence for the crystallization of magnons below the saturation field at non-zero temperatures for the highly frustrated spin-half kagome Heisenberg antiferromagnet. This phenomenon can be traced back to the existence of independent localized magnons or equivalently flat-band multi-magnon states. We present a loop-gas description of these localized magnons and a phase diagram of this transition, thus providing information for which magnetic fields and temperatures magnon crystallization can be observed experimentally. The emergence of a finite-temperature continuous transition to a magnon-crystal is expected to be generic for spin models in dimension $D>1$ where flat-band multi-magnon ground states break translational symmetry.

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J. Schnack, J. Schulenburg, A. Honecker, J. Richter. 2019-10-23. Magnon crystallization in the kagome lattice antiferromagnet. https://doi.org/10.1103/physrevlett.125.117207

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