Domain-wall-induced electromagnons in multiferroics

S Sayedaghaee (1) , Sergey Prosandeev (1) , Sergei Prokhorenko (1) , Yousra Nahas (1) , Charles Paillard (2) , Bin Xu (3) , L Bellaiche (1)

1 Institute for nanosciences and engineering and physics departement [University of Arkansas]
2 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides
3 Institute of Theoretical and Applied Physics and School of Physical Science and Technology Soochow University, Suzhou, Jiangsu 215006, China

Using an atomistic approach, we predict the emergence of new hybrid quasi-particles, namely domain-wall-induced electromagnons, that arise from dynamical couplings between magnons and optical phonons in systems possessing ferroelectric domain walls. These quasi-particles induce THz resonances in magnetoelectric responses and preferentially localize either near the domain walls or near the middle of domains. Such behavior is explained through dispersion analysis that allows to track the emergent multi-domain excitations back to single-domain magnetoelectric (ME) modes. The latter, scattered by a periodic array of domain walls, are shown to endow the domainwall-induced electromagnons with a mixed localized mode and a standing-or propagating-wave characters. Such features can be exploited to reach strikingly large ME conversion and designing more reliable and ultrafast ME devices with less energy consumption and using, e.g., local probes.

Domaines: Physique [physics]

S Sayedaghaee, Sergey Prosandeev, Sergei Prokhorenko, Yousra Nahas, Charles Paillard, et al.. Domain-wall-induced electromagnons in multiferroics. Physical Review Materials, 2022, 6 (3), pp.034403. ⟨10.1103/PhysRevMaterials.6.034403⟩. ⟨hal-03618401⟩