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Tunneling spectroscopy for ferromagnet/superconductor junctions

Igor Zutic·Oriol T. Valls
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Abstract

In tunneling spectroscopy studies of ferromagnet/superconductor (F/S) junctions, the effects of spin polarization, Fermi wavevector mismatch (FWM) between the F and S regions, and interfacial resistance play a crucial role. We study the low bias conductance spectrum of these junctions, governed by Andreev reflection at the F/S interface. We consider both d- and s-wave superconductors as well as mixed states of the $d+is$ form. We present results for a range of values of the relevant parameters and find that a rich variety of features appears, depending on pairing state and other conditions. We show that in the presence of FWM, spin polarization can enhance Andreev reflection and give rise to a zero bias conductance peak for an s-wave superconductor.

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Igor Zutic, Oriol T. Valls. 1999-02-07. Tunneling spectroscopy for ferromagnet/superconductor junctions. https://doi.org/10.1103/physrevb.61.1555

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