Article

Highly Spin-Polarized Room-Temperature Tunnel Injector for Semiconductor Spintronics using MgO(100)

Solid State and Photonics Laboratory, Stanford University, Palo Alto, California, United States
Physical Review Letters (Impact Factor: 7.51). 03/2005; 94(5):056601. DOI: 10.1103/PhysRevLett.94.056601
Source: PubMed

ABSTRACT

The spin polarization of current injected into GaAs from a CoFe/MgO(100) tunnel injector is inferred from the electroluminescence polarization from GaAs/AlGaAs quantum well detectors. The polarization reaches 57% at 100 K and 47% at 290 K in a 5 T perpendicular magnetic field. Taking into account the field dependence of the luminescence polarization, the spin injection efficiency is at least 52% at 100 K, and 32% at 290 K. We find a nonmonotonic temperature dependence of the polarization which can be attributed to spin relaxation in the quantum well detectors.

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Available from: James S Harris, Dec 31, 2013
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