Stroboscopic Kerr imaging of magnetoacoustic waves in ferromagnetic thin films

In this work, we develop a Stroboscopic Kerr Microscope capable of visualizing both surface acoustic waves (SAWs) and magnetoacoustic waves (MAWs). The setup combines the magnetic contrast sensitivity of MOKE microscopy with the temporal resolution of stroboscopic imaging, as well as uniform illumin...

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Detalles Bibliográficos
Autor: Castellví Picanyol, Anna
Tipo de recurso: tesis de maestría
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/452402
Acceso en línea:https://hdl.handle.net/2117/452402
Access Level:acceso abierto
Palabra clave:Acoustic surface waves
Microscopy
Magnetoacoustic waves
Stroboscopic Kerr microscopy
Magnetoelastic coupling
Surface acoustic waves
Ferromagnetic thin films
Spintronics
Ones acústiques de superfície
Microscòpia
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Telecomunicació òptica::Fotònica
Descripción
Sumario:In this work, we develop a Stroboscopic Kerr Microscope capable of visualizing both surface acoustic waves (SAWs) and magnetoacoustic waves (MAWs). The setup combines the magnetic contrast sensitivity of MOKE microscopy with the temporal resolution of stroboscopic imaging, as well as uniform illumination achieved through a multimode fiber and a despeckler. We obtained SAW images at 124, 248, and 371 MHz, and focused on MAW imaging at 124 MHz, in stripe widths of 200 µm. Furthermore, the flexibility of the system allows us to quantify the magnetization tilt amplitude under a magnetic field sweep and to study its angular dependence. Tilt amplitudes of up to 30% of full switching are observed in the nickel layer.