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Positive cross-correlations induced by ferromagnetic contacts

Fabio Taddei·Rosario Fazio
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Abstract

Due to the Fermionic nature of carriers, correlations between electric currents flowing through two different contacts attached to a conductor present a negative sign. Possibility for positive cross-correlations has been demonstrated in hybrid normal/superconductor structures under certain conditions. In this paper we show that positive cross-correlations can be induced, if not already present, in such structures by employing ferromagnetic leads with magnetizations aligned anti-parallel to each other. We consider three-terminal hybrid structures and calculate the mean-square correlations of current fluctuations as a function of the bias voltage at finite temperature.

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Fabio Taddei, Rosario Fazio. 2002-02-22. Positive cross-correlations induced by ferromagnetic contacts. https://doi.org/10.1103/physrevb.65.134522

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