Negative four-terminal resistance as a probe of crossed Andreev reflection

D. Beckmann H. v. Löhneysen

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Negative four-terminal resistance as a probe of crossed Andreev reflection

D. Beckmann H. v. Löhneysen

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Abstract

We report on the experimental investigation of electronic transport in superconductor-ferromagnet spin-valve structures. Our samples consist of two ferromagnetic iron leads forming planar tunnel contacts to a superconducting aluminum wire. At energies below the superconducting gap, we observe a negative four-probe resistance that can be explained by crossed Andreev reflection.

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D. Beckmann H. v. Löhneysen. 2006-09-29. Negative four-terminal resistance as a probe of crossed Andreev reflection. https://arxiv.org/abs/cond-mat/0609766

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