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arXiv · 0810.4390

Local control of spin flow in weak magnetic fields

J. -H. Quast·G. V. Astakhov·W. Ossau·L. W. Molenkamp·J. Heinrich·S. Hofling·A. Forchel
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Abstract

We demonstrate that optical illumination strongly influences spin transport in n-type GaAs. Specifically, increasing the power density of optical spin pumping results in a significant expansion of the spin diffusion profile. A further means of manipulation is the application of a weak transverse magnetic field, which strongly increases spin flow out of the excitation spot. These effects are directly monitored in spin imaging experiments and spatially resolved Hanle measurements.

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J. -H. Quast, G. V. Astakhov, W. Ossau, L. W. Molenkamp, J. Heinrich, S. Hofling, A. Forchel. 2008-10-24. Local control of spin flow in weak magnetic fields. https://arxiv.org/abs/0810.4390

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