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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
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Magnetic excitations beyond the single- and double-magnons
Hebatalla Elnaggar1,2, Abhishek Nag3, Maurits W Haverkort4
1Debye Institute for Nanomaterials Science, Utrecht University, 3584 CA, Utrecht, The Netherlands. hebatalla.elnaggar@sorbonne-universite.fr.
Nature Communications
|May 12, 2023
Summary
Researchers observed triple-magnon excitations in iron oxide, challenging the conventional understanding of magnetic system spin manipulation. This discovery opens new avenues for higher-rank magnons in magnon-based technologies.
Area of Science:
- Condensed Matter Physics
- Quantum Magnetism
- Materials Science
Background:
- A single photon can alter magnetic spin by one unit (ΔMs=±1).
- Two-photon scattering is conventionally understood to affect spin by a maximum of two units.
- Resonant inelastic X-ray scattering (RIXS) typically reveals 1- and 2-magnon excitations.
Purpose of the Study:
- To investigate higher-order magnon excitations beyond the conventional understanding.
- To explore the possibility of exciting more than two magnons simultaneously.
- To understand the underlying mechanisms of exotic magnon excitations.
Main Methods:
- Resonant inelastic X-ray scattering (RIXS) experiments on α-Fe2O3.
- Theoretical calculations to model the observed phenomena.
- Analysis of excitation energies and their relation to magnon energy.
Main Results:
- Observation of a triple-magnon excitation at three times the magnon energy in α-Fe2O3.
- Detection of quadruple and quintuple-magnon excitations at four and five times the magnon energy.
- Experimental evidence contradicting the conventional limit of 2-magnon excitations.
Conclusions:
- Two-photon scattering can create exotic higher-rank magnons (triple, quadruple, quintuple).
- These higher-rank magnons are relevant for advanced magnon-based applications.
- The findings expand the understanding of light-matter interactions in magnetic systems.
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