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Bipolar spin filter in a quantum dot molecule

F. Mireles·E. Cota·F. Rojas·S. E. Ulloa
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Abstract

We show that the tunable hybridization between two lateral quantum dots connected to non-magnetic current leads in a `hanging-dot' configuration that can be used to implement a bipolar spin filter. The competition between Zeeman, exchange interaction, and interdot tunneling (molecular hybridization) yields a singlet-triplet transition of the double dot {\it ground state} that allows spin filtering in Coulomb blockade experiments. Its generic nature should make it broadly useful as a robust bidirectional spin polarizer.

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F. Mireles, E. Cota, F. Rojas, S. E. Ulloa. 2006-02-17. Bipolar spin filter in a quantum dot molecule. https://doi.org/10.1063/1.2175487

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