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arXiv · 2212.07994

Resonant and off-resonant magnetoacoustic waves in epitaxial Fe$_3$Si/GaAs hybrid structures

Marc Rovirola·M. Waqas Khaliq·Blai Casals·Michael Foerster·Miguel Angel Niño·Jens Herfort·Joan Manel Hernàndez·Ferran Macià·Alberto Hernández-Mínguez
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Abstract

Surface acoustic waves (SAWs) provide an efficient dynamical coupling between strain and magnetization in micro/nano-metric devices. Using a hybrid device composed of a piezoelectric, GaAs, and a ferromagnetic Heusler alloy thin film, Fe$_3$Si, we are able to quantify the amplitude of magnetoacoustic waves generated with SAWs via magnetic imaging in an X-ray photoelectron microscope. The cubic anisotropy of the sample together with a low damping coefficient allows for the observation of resonant and non-resonant magnetoelastic coupling. Additionally, via micromagnetic simulation, we verify the experimental behavior and quantify the magnetoelastic shear strain component in Fe$_3$Si that appears to be very large ($b_2=14\times 10^6$ J/m$^3$), much larger than the one found in Nickel.

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Marc Rovirola, M. Waqas Khaliq, Blai Casals, Michael Foerster, Miguel Angel Niño, Jens Herfort, Joan Manel Hernàndez, Ferran Macià, Alberto Hernández-Mínguez. 2022-12-15. Resonant and off-resonant magnetoacoustic waves in epitaxial Fe$_3$Si/GaAs hybrid structures. https://arxiv.org/abs/2212.07994

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