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arXiv · 1108.4907

Field-induced negative differential spin lifetime in silicon

Jing Li·Lan Qing·Hanan Dery·Ian Appelbaum
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Abstract

We show that the electric field-induced thermal asymmetry between the electron and lattice systems in pure silicon substantially impacts the identity of the dominant spin relaxation mechanism. Comparison of empirical results from long-distance spin transport devices with detailed Monte-Carlo simulations confirms a strong spin depolarization beyond what is expected from the standard Elliott-Yafet theory already at low temperatures. The enhanced spin-flip mechanism is attributed to phonon emission processes during which electrons are scattered between conduction band valleys that reside on different crystal axes. This leads to anomalous behavior, where (beyond a critical field) reduction of the transit time between spin-injector and spin-detector is accompanied by a counterintuitive reduction in spin polarization and an apparent negative spin lifetime.

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Jing Li, Lan Qing, Hanan Dery, Ian Appelbaum. 2011-08-24. Field-induced negative differential spin lifetime in silicon. https://doi.org/10.1103/physrevlett.108.157201

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