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arXiv · 1403.4509

Exchange-driven magnetoresistance in silicon facilitated by electrical spin injection

Yuichiro Ando·Lan Qing·Yang Song·Shinya Yamada·Kenji Kasahara·Kentarou Sawano·Masanobu Miyao·Hanan Dery·Kohei Hamaya
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Abstract

We use electrical spin injection to probe exchange interactions in phosphorus doped silicon (Si:P). The detection is enabled by a magnetoresistance effect that demonstrates the efficiency of exchange in imprinting spin information from the magnetic lead onto the localized moments in the Si:P region. A unique Lorentzian-shaped signal existing only at low temperatures ($\lesssim 25 K$) is observed experimentally and analyzed theoretically in electrical Hanle effect measurement. It stems from spin-dependent scattering of electrons by neutral impurities in Si:P. The shape of this signal is not directly related to spin relaxation but to exchange interaction between spin-polarized electrons that are localized on adjacent impurities.

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Yuichiro Ando, Lan Qing, Yang Song, Shinya Yamada, Kenji Kasahara, Kentarou Sawano, Masanobu Miyao, Hanan Dery, Kohei Hamaya. 2014-03-18. Exchange-driven magnetoresistance in silicon facilitated by electrical spin injection. https://arxiv.org/abs/1403.4509

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