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Negative Magnetoresistance in Andreev Interferometers

W. Belzig·R. Shaikaidarov·V. V. Petrashov·Yu. V. Nazarov
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Abstract

We consider transport in a diffusive cross-shaped Andreev interferometer geometry, both theoretically and experimentally. A strong and unexpected modulation of the conductance with the superconducting phase is found. In particular, a reversed resistance vs. phase difference is predicted, where the resistance is decreased by a phase gradient. A comparison of our quasiclassical calculation with experimental data shows quantitative agreement if we account for diamagnetic screening.

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W. Belzig, R. Shaikaidarov, V. V. Petrashov, Yu. V. Nazarov. 2002-03-26. Negative Magnetoresistance in Andreev Interferometers. https://doi.org/10.1103/physrevb.66.220505

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