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Magnetic excitations beyond the single- and double-magnons.

ABSTRACT: A photon carrying one unit of angular momentum can change the spin angular momentum of a magnetic system with one unit (ΔM_s = ±1) at most. This implies that a two-photon scattering process can manipulate the spin angular momentum of the magnetic system with a maximum of two units. Herein we describe a triple-magnon excitation in α-Fe₂O₃, which contradicts this conventional wisdom that only 1- and 2-magnon excitations are possible in a resonant inelastic X-ray scattering experiment. We observe an excitation at exactly three times the magnon energy, along with additional excitations at four and five times the magnon energy, suggesting quadruple and quintuple-magnons as well. Guided by theoretical calculations, we reveal how a two-photon scattering process can create exotic higher-rank magnons and the relevance of these quasiparticles for magnon-based applications.

SUBMITTER: Elnaggar H

PROVIDER: S-EPMC10182046 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Magnetic excitations beyond the single- and double-magnons.

Elnaggar Hebatalla H Nag Abhishek A Haverkort Maurits W MW Garcia-Fernandez Mirian M Walters Andrew A Wang Ru-Pan RP Zhou Ke-Jin KJ de Groot Frank F

Nature communications 20230512 1

A photon carrying one unit of angular momentum can change the spin angular momentum of a magnetic system with one unit (ΔMs = ±1) at most. This implies that a two-photon scattering process can manipulate the spin angular momentum of the magnetic system with a maximum of two units. Herein we describe a triple-magnon excitation in α-Fe2O3, which contradicts this conventional wisdom that only 1- and 2-magnon excitations are possible in a resonant inelastic X-ray sca ...[more]

PMID: 37173301

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