Local control of spin flow in weak magnetic fields

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

Local control of spin flow in weak magnetic fields

Authors

Description

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.