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arXiv · 1106.4619

Spin dephasing in Silicon Germanium nanowires

Ashish Kumar·Bahniman Ghosh
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Abstract

We study spin polarized transport in silicon germanium nanowires using a semiclassical monte carlo approach. Spin depolarization in the channel is caused due to D'yakonov-Perel (DP) relaxation associated with Rashba spin orbit coupling and due to Elliott- Yafet (EY) relaxation. We investigate the dependence of spin dephasing on germanium mole fraction in silicon germanium nanowires. The spin dephasing lengths decrease with an increase in the germanium mole fraction. We also find that the temperature has a strong influence on the dephasing rate and spin relaxation lengths increase with decrease in temperature. The ensemble averaged spin components and the steady state distribution of spin components vary with initial polarization.

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Ashish Kumar, Bahniman Ghosh. 2011-06-23. Spin dephasing in Silicon Germanium nanowires. https://doi.org/10.1063/1.3666022

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