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arXiv · 0705.4215

Non local Andreev reflection in a carbon nanotube superconducting quantum interference device

S. Duhot·R. Mélin
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Abstract

We investigate a superconducting quantum interference device (SQUID) based on carbon nanotubes in a fork geometry [J.-P. Cleuziou {\it et al.}, Nature Nanotechnology {\bf 1}, 53 (2006)], involving tunneling of evanescent quasiparticles through a superconductor over a distance comparable to the superconducting coherence length, with therefore ``non local'' processes generalizing non local Andreev reflection and elastic cotunneling. Non local processes induce a reduction of the critical current and modify the current-phase relation. We discuss arbitrary interface transparencies. Such devices in fork geometries are candidates for probing the phase coherence of crossed Andreev reflection.

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S. Duhot, R. Mélin. 2007-10-19. Non local Andreev reflection in a carbon nanotube superconducting quantum interference device. https://doi.org/10.1103/physrevb.77.014525

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