Tunable Spin Filtering through an Aluminum Nanoparticle

F. T. Birk; C. E. Malec; D. Davidovic

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arXiv · 0809.2239

Tunable Spin Filtering through an Aluminum Nanoparticle

F. T. Birk·C. E. Malec·D. Davidovic

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Abstract

Spin-polarized current through an Al nanoparticle in tunnel contact with two ferromagnets is measured as a function of the direction of the applied magnetic field. The nanoparticle filters the spin of injected electrons along a direction specified by the magnetic field. The characteristic field scale for the filtering corresponds to a lower limit of $8ns$ for the spin-dephasing time. Spin polarized current versus applied voltage increases stepwise, confirming that the spin relaxation time is long only in the ground state and the low-lying excited states of the nanoparticle.

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F. T. Birk, C. E. Malec, D. Davidovic. 2008-09-12. Tunable Spin Filtering through an Aluminum Nanoparticle. https://arxiv.org/abs/0809.2239

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