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Detecting Spin-Polarized Currents in Ballistic Nanostructures

R. M. Potok·J. A. Folk·C. M. Marcus·V. Umansky
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Abstract

We demonstrate a mesoscopic spin polarizer/analyzer system that allows the spin polarization of current from a quantum point contact in an in-plane magnetic field to be measured. A transverse focusing geometry is used to couple current from an emitter point contact into a collector point contact. At large in-plane fields, with the point contacts biased to transmit only a single spin (g < e^2/h), the voltage across the collector depends on the spin polarization of the current incident on it. Spin polarizations of greater than 80% are found for both emitter and collector at 300mK and 7T in-plane field.

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R. M. Potok, J. A. Folk, C. M. Marcus, V. Umansky. 2002-06-19. Detecting Spin-Polarized Currents in Ballistic Nanostructures. https://doi.org/10.1103/physrevlett.89.266602

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