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Spin-Polarized Electron Transport through Nanometer-Scale Al Grains

L. Y. Zhang·C. Y. Wang·Y. G. Wei·X. Y. Liu·D. Davidovic
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Abstract

We investigate spin-polarized electron tunnelling through ensembles of nanometer scale Al grains embedded between two Co-reservoirs at 4.2K, and observe tunnelling-magnetoresistance (TMR) and effects from spin-precession in the perpendicular applied magnetic field (the Hanle effect). The spin-coherence time ($T_2^\star$) measured using the Hanle effect is of order $ns$. The dephasing is attributed to electron spin-precession in local magnetic fields. Dephasing process does not destroy $TMR$, which is strongly asymmetric with bias voltage. The asymmetric TMR is explained by spin relaxation in Al grains and asymmetric electron dwell times.

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L. Y. Zhang, C. Y. Wang, Y. G. Wei, X. Y. Liu, D. Davidovic. 2005-12-01. Spin-Polarized Electron Transport through Nanometer-Scale Al Grains. https://doi.org/10.1103/physrevb.72.155445

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