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Positive cross-correlations in a three-terminal quantum dot with ferromagnetic contacts

A. Cottet·W. Belzig·C. Bruder
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Abstract

We study current fluctuations in an interacting three-terminal quantum dot with ferromagnetic leads. For appropriately polarized contacts, the transport through the dot is governed by a novel dynamical spin blockade, i.e., a spin-dependent bunching of tunneling events not present in the paramagnetic case. This leads for instance to positive zero-frequency cross-correlations of the currents in the output leads even in the absence of spin accumulation on the dot. We include the influence of spin-flip scattering and identify favorable conditions for the experimental observation of this effect with respect to polarization of the contacts and tunneling rates.

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A. Cottet, W. Belzig, C. Bruder. 2004-03-19. Positive cross-correlations in a three-terminal quantum dot with ferromagnetic contacts. https://doi.org/10.1103/physrevlett.92.206801

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