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RESEARCH PRODUCT
Ultrafast amplification and non-linear magneto-elastic coupling of coherent magnon modes in an antiferromagnet
Takuya SatohD. BossiniMirko CinchettiMatteo PancaldiMartina BasiniOlena GomonayLucile SoumahStefano BonettiStefano BonettiFabian Mertenssubject
Terahertz radiationFOS: Physical sciencesGeneral Physics and AstronomyPhysics::Optics02 engineering and technologyPhoton energy01 natural sciencesSettore FIS/03 - Fisica della MateriaCondensed Matter::Materials Sciencesymbols.namesakeMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesAntiferromagnetism010306 general physicsPhysicsCondensed matter physicsSpinsCondensed Matter - Mesoscale and Nanoscale PhysicsCondensed Matter::OtherMagnonResonance021001 nanoscience & nanotechnology3. Good healthCondensed Matter - Other Condensed MatterCoupling (physics)symbolsCondensed Matter::Strongly Correlated Electrons0210 nano-technologyHamiltonian (quantum mechanics)Other Condensed Matter (cond-mat.other)description
We investigate the role of domain walls in the ultrafast magnon dynamics of an antiferromagnetic NiO single crystal in a pump-probe experiment with variable pump photon energy. Analysing the amplitude of the energy-dependent photo-induced ultrafast spin dynamics, we detect a yet unreported coupling between the material's characteristic THz- and a GHz-magnon modes. We explain this unexpected coupling between two orthogonal eigenstates of the corresponding Hamiltonian by modelling the magneto-elastic interaction between spins in different domains. We find that such interaction, in the non-linear regime, couples the two different magnon modes via the domain walls and it can be optically exploited via the exciton-magnon resonance.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2021-03-20 |