Local characterization of ferromagnetic properties in ferromagnet/superconductor bilayer by Point Contact Andreev Reflection Spectroscopy

Filippo Giubileo; Francesco Romeo; Roberta Citro; Antonio Di Bartolomeo; Carmine Attanasio; Carla Cirillo; Albino Polcari; Paola Romano

doi:10.1038/srep17544

arXiv · 1407.4906

Local characterization of ferromagnetic properties in ferromagnet/superconductor bilayer by Point Contact Andreev Reflection Spectroscopy

Filippo Giubileo·Francesco Romeo·Roberta Citro·Antonio Di Bartolomeo·Carmine Attanasio·Carla Cirillo·Albino Polcari·Paola Romano

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Abstract

We realized point contact spectroscopy experiment on ferromagnet/superconductor bilayers. Differential conductance curves show several features that we explained within Bogoliubov-de Gennes formalism considering the presence of two interfaces in the normal-metal-tip/ferromagnet/superconductor device. We demonstrate that such configuration is suitable as local probe of the spin polarization and thickness of ferromagnetic layer, directly on bilayer areas. This is due to the high sensitivity of the Andreev surface states to the physical properties of the ferromagnetic interlayer.

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Filippo Giubileo, Francesco Romeo, Roberta Citro, Antonio Di Bartolomeo, Carmine Attanasio, Carla Cirillo, Albino Polcari, Paola Romano. 2014-07-18. Local characterization of ferromagnetic properties in ferromagnet/superconductor bilayer by Point Contact Andreev Reflection Spectroscopy. https://doi.org/10.1038/srep17544

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