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arXiv · 0906.3679

Resonant spin transport through a superconducting double barrier structure

Arijit Kundu·Sumathi Rao·Arijit Saha
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Abstract

We study resonant transport through a superconducting double barrier structure. At each barrier, due to the proximity effect, an incident electron can either reflect as an electron or a hole (Andreev reflection). Similarly, transport across the barrier can occur via direct tunneling as electrons as well as via the crossed Andreev channel, where a hole is transmitted. In the subgap regime, for a symmetric double barrier system (with low transparency for each barrier), we find a new T=1/4 resonance (T is the transmission probability for electrons incident on the double barrier structure) due to interference between electron and hole wave-functions between the two barriers, in contrast to a normal double barrier system which has the standard transmission resonance at T=1. We also point out as an application that the resonant value of T=1/4 can produce pure spin current through the superconducting double barrier structure.

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Arijit Kundu, Sumathi Rao, Arijit Saha. 2009-06-19. Resonant spin transport through a superconducting double barrier structure. https://doi.org/10.1209/0295-5075/88/57003

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