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arXiv · 1903.05097

Magnon Landau levels and emergent supersymmetry in strained antiferromagnets

Mary Madelynn Nayga·Stephan Rachel·Matthias Vojta
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Abstract

Inhomogeneous strain applied to lattice systems can induce artificial gauge fields for particles moving on this lattice. Here we demonstrate how to engineer a novel state of matter, namely an antiferromagnet with a Landau-level excitation spectrum of magnons. We consider a honeycomb-lattice Heisenberg model and show that triaxial strain leads to equally spaced pseudo-Landau levels at the upper end of the magnon spectrum, with degeneracies characteristic of emergent supersymmetry. We also present a particular strain protocol which induces perfectly quantized magnon Landau levels over the whole bandwidth. We discuss experimental realizations and generalizations.

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Mary Madelynn Nayga, Stephan Rachel, Matthias Vojta. 2019-09-05. Magnon Landau levels and emergent supersymmetry in strained antiferromagnets. https://doi.org/10.1103/physrevlett.123.207204

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