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arXiv · 1007.0233

The Larmor clock and anomalous spin dephasing in silicon

Biqin Huang·Ian Appelbaum
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Abstract

Drift-diffusion theory - which fully describes charge transport in semiconductors - is also universally used to model transport of spin-polarized electrons in the presence of longitudinal electric fields. By transforming spin transit time into spin orientation with precession (a technique called the "Larmor clock") in current-sensing vertical-transport intrinsic Si devices, we show that spin diffusion (and concomitant spin dephasing) can be greatly enhanced with respect to charge diffusion, in direct contrast to predictions of spin Coulomb-drag diffusion suppression.

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Biqin Huang, Ian Appelbaum. 2010-09-28. The Larmor clock and anomalous spin dephasing in silicon. https://doi.org/10.1103/physrevb.82.241202

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