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arXiv · 1007.4653

Focused Crossed Andreev Reflection

Håvard Haugen·Arne Brataas·Xavier Waintal·Gerrit E. W. Bauer
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Abstract

We consider non-local transport in a system with one superconducting and two normal metal terminals. Electron focusing by weak perpendicular magnetic fields is shown to tune the ratio between crossed Andreev reflection (CAR) and electron transfer (ET) in the non-local current response. Additionally, electron focusing facilitates non-local signals between normal metal contacts where the separation is as large as the mean free path rather than being limited by the coherence length of the superconductor. CAR and ET can be selectively enhanced by modulating the magnetic field.

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Håvard Haugen, Arne Brataas, Xavier Waintal, Gerrit E. W. Bauer. 2010-07-27. Focused Crossed Andreev Reflection. https://doi.org/10.1209/0295-5075%2F93%2F67005

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