Zero-field 29Si nuclear magnetic resonance signature of helimagnons in MnSi

TL;DR

This paper interprets low-temperature NMR data in MnSi as evidence of helimagnon excitations, confirming theoretical predictions of their gapless, anisotropic dispersion and aligning with other experimental techniques.

Contribution

It provides experimental confirmation of helimagnon dispersion in MnSi through zero-field 29Si NMR measurements, supporting theoretical models.

Findings

Confirmation of gapless, anisotropic helimagnon dispersion

Quantitative agreement with neutron scattering and muon spin results

Validation of NMR as a probe for helimagnon excitations

Abstract

The low temperature dependence of the nuclear magnetic resonance frequency and spin-lattice relaxation rate measured in the chiral magnet MnSi by Yasuoka and coworkers [J. Phys. Soc. Jpn. 85, 073701 (2016)] is interpreted in terms of helimagnon excitations. The theoretically predicted gapless and anisotropic dispersion relation which is probed at extremely small energy is experimentally confirmed. Whenever comparison is possible, the results are found quantitatively consistent with those of the inelastic neutron scattering and muon spin rotation and relaxation techniques. Further studies are suggested.