Experimental Evidence for Crossed Andreev Reflection

D. Beckmann; H. v. Löhneysen

doi:10.1063/1.2354983

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arXiv · cond-mat/0512445

Experimental Evidence for Crossed Andreev Reflection

D. Beckmann·H. v. Löhneysen

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Abstract

We report on electronic transport properties of mesoscopic superconductor-ferromagnet spin-valve structures. Two ferromagnetic iron leads form planar tunnel contacts to a superconducting aluminum wire, where the distance of the two contacts is of the order of the coherence length of the aluminum. We observe a negative non-local resistance which can be explained by crossed Andreev reflection, a process where an electron incident from one of the leads gets reflected as a hole into the other, thereby creating a pair of spatially separated, entangled particles.

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D. Beckmann, H. v. Löhneysen. 2005-12-19. Experimental Evidence for Crossed Andreev Reflection. https://doi.org/10.1063/1.2354983

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