Quantitative magneto-optical investigation of superconductor/ferromagnet hybrid structures

G. Shaw (1) , J. Brisbois (1) , L. B G L Pinheiro (2) , J. Müller (1) , S. Blanco Alvarez (1) , Thibaut Devillers (3) , Nora Dempsey (3) , J. E Scheerder (4) , J. van de Vondel (4) , S. Melinte (4) , P. Vanderbemden (1) , M. Motta (5) , W. A Ortiz (5) , Klaus Hasselbach (6) , R. B. G. Kramer (7) , A. V Silhanek (1)

1 Université de Liège
2 UFSCar - Universidade Federal de São Carlos [São Carlos]
3 NEEL - MNM - Micro et NanoMagnétisme
4 KU Leuven - Catholic University of Leuven = Katholieke Universiteit Leuven
5 UFSCar - Federal University of São Carlos
6 NEEL - MagSup - Magnétisme et Supraconductivité
7 NEEL - QuantECA - Circuits électroniques quantiques Alpes

We present a detailed quantitative magneto-optical imaging study of several superconductor/ferromagnet hybrid structures, including Nb deposited on top of thermomagnetically patterned NdFeB, and permalloy/niobium with erasable and tailored magnetic landscapes imprinted in the permalloy layer. The magneto-optical imaging data is complemented with and compared to scanning Hall probe microscopy measurements. Comprehensive protocols have been developed for calibrating, testing, and converting Faraday rotation data to magnetic field maps. Applied to the acquired data, they reveal the comparatively weaker magnetic response of the superconductor from the background of larger fields and field gradients generated by the magnetic layer.

Domaines: Instrumentations et Détecteurs [physics.ins-det]

G. Shaw, J. Brisbois, L. B G L Pinheiro, J. Müller, S. Blanco Alvarez, et al.. Quantitative magneto-optical investigation of superconductor/ferromagnet hybrid structures. Review of Scientific Instruments, 2018, 89 (2), pp.023705. ⟨10.1063/1.5016293⟩. ⟨hal-03271250v2⟩