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Mesoscopic Stern-Gerlach spin filter by nonuniform spin-orbit interaction

Jun-ichiro Ohe·Masayuki Yamamoto·Tomi Ohtsuki·Junsaku Nitta
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Abstract

A novel spin filtering in two-dimensional electron system with nonuniform spin-orbit interactions (SOI) is theoretically studied. The strength of SOI is modulated perpendicular to the charge current. A spatial gradient of effective magnetic field due to the nonuniform SOI causes the Stern-Gerlach type spin separation. The direction of the polarization is perpendicular to the current and parallel to the spatial gradient. Almost 100 % spin polarization can be realized even without applying any external magnetic fields and without attaching ferromagnetic contacts. The spin polarization persists even in the presence of randomness.

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Jun-ichiro Ohe, Masayuki Yamamoto, Tomi Ohtsuki, Junsaku Nitta. 2005-06-14. Mesoscopic Stern-Gerlach spin filter by nonuniform spin-orbit interaction. https://doi.org/10.1103/physrevb.72.041308

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