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arXiv · 2010.08425

Zero-magnon sound in quantum Heisenberg ferromagnets

Raphal Goll·Andreas Rückriegel·Peter Kopietz
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Abstract

Using a functional renormalization group approach we show that at low temperatures and in a certain range of magnetic fields the longitudinal dynamic structure factor of quantum Heisenberg ferromagnets in dimensions $D\leq 2$ exhibits a well-defined quasi-particle peak with linear dispersion that we identify as zero-magnon sound. In $D>2$ the larger phase space available for the decay into transverse spin waves leads only to a broad hump centered at zero frequency whose width scales linearly in momentum.

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BibTeXRIS

Raphal Goll, Andreas Rückriegel, Peter Kopietz. 2021-01-11. Zero-magnon sound in quantum Heisenberg ferromagnets. https://doi.org/10.1103/physrevb.102.224437

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