Splitting electronic spins with a Kondo double dot device

Denis Feinberg; Pascal Simon

doi:10.1063/1.1784878

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Splitting electronic spins with a Kondo double dot device

Denis Feinberg·Pascal Simon

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Abstract

We present a simple device made of two small capacitively coupled quantum dots in parallel. This set-up can be used as an efficient "Stern-Gerlach" spin filter, able to simultaneously produce, from a normal metallic lead, two oppositely spin-polarized currents when submitted to a local magnetic field. Our proposal is based on the realization of a Kondo effect where spin and orbital degrees of freedom are entangled, allowing a spatial separation between the two spin polarized currents. In the low temperature Kondo regime, the efficiency is very high and the device conductance reaches the unitary limit, $\frac{e^2}{h}$ per spin branch.

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Denis Feinberg, Pascal Simon. 2004-09-14. Splitting electronic spins with a Kondo double dot device. https://doi.org/10.1063/1.1784878

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