Superconducting/ferromagnetic hybrid structures with spin-active interfaces

Audrey Cottet (1)

1 LPA - Laboratoire Pierre Aigrain

The Spin-Dependence of Interfacial Phase Shifts (SDIPS) acquired by electrons upon scattering on superconductor/ferromagnet interfaces can strongly modify the behaviour of superconducting/ferromagnetic hybrid structures. We have studied the case of ballistic quantum point contacts and the case of diffusive hybrid systems. For the first type of system, the SDIPS can induce sub-gap resonances in the conductance and differential Fano factor [1]. It can also produce characteristic steps in the current noise curves versus frequency [2]. For the second type of system, the SDIPS can modify the superconducting proximity effect, through a phase-shifting of the spatial oscillations of the superconducting order parameter in the ferromagnetic layers [3,4], or through the appearance of effective Zeeman fields in the superconducting layers [4]. [1] A. Cottet and W. Belzig, Phys. Rev. B 77, 064517 (2008). [2] A. Cottet, B. Douçot and W. Belzig, arXiv:0803.0854 [3] A. Cottet and W. Belzig, Phys. Rev. B 72, 180503(R) (2005). [4] A. Cottet, Phys. Rev. B 76, 224505 (2007).

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Audrey Cottet. Superconducting/ferromagnetic hybrid structures with spin-active interfaces. 420th Wilhelm und Else Heraeus Seminar "Unconventional Proximity Effects in Novel Materials", Oct 2008, Bad Honnef, Germany. ⟨hal-00400401⟩