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arXiv · 0901.2183

Spin injection in Silicon at zero magnetic field

L. Grenet·M. Jamet·P. Noé·V. Calvo·J. -M. Hartmann·L. E. Nistor·B. Rodmacq·S. Auffret·P. Warin·Y. Samson
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Abstract

In this letter, we show efficient electrical spin injection into a SiGe based \textit{p-i-n} light emitting diode from the remanent state of a perpendicularly magnetized ferromagnetic contact. Electron spin injection is carried out through an alumina tunnel barrier from a Co/Pt thin film exhibiting a strong out-of-plane anisotropy. The electrons spin polarization is then analysed through the circular polarization of emitted light. All the light polarization measurements are performed without an external applied magnetic field \textit{i.e.} in remanent magnetic states. The light polarization as a function of the magnetic field closely traces the out-of-plane magnetization of the Co/Pt injector. We could achieve a circular polarization degree of the emitted light of 3 % at 5 K. Moreover this light polarization remains almost constant at least up to 200 K.

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L. Grenet, M. Jamet, P. Noé, V. Calvo, J. -M. Hartmann, L. E. Nistor, B. Rodmacq, S. Auffret, P. Warin, Y. Samson. 2009-01-15. Spin injection in Silicon at zero magnetic field. https://doi.org/10.1063/1.3064135

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