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Energy-resolved electron-spin dynamics at surfaces of p-doped GaAs

H. C. Schneider·J. -P. Wuestenberg·O. Andreyev·K. Hiebbner·L. Guo·J. Lange·L. Schreiber·B. Beschoten·M. Bauer·M. Aeschlimann
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Abstract

Electron-spin relaxation at different surfaces of p-doped GaAs is investigated by means of spin, time and energy resolved 2-photon photoemission. These results are contrasted with bulk results obtained by time-resolved Faraday rotation measurements as well as calculations of the Bir-Aronov-Pikus spin-flip mechanism. Due to the reduced hole density in the band bending region at the (100) surface the spin-relaxation time increases over two orders of magnitude towards lower energies. At the flat-band (011) surface a constant spin relaxation time in agreement with our measurements and calculations for bulk GaAs is obtained.

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H. C. Schneider, J. -P. Wuestenberg, O. Andreyev, K. Hiebbner, L. Guo, J. Lange, L. Schreiber, B. Beschoten, M. Bauer, M. Aeschlimann. 2005-08-25. Energy-resolved electron-spin dynamics at surfaces of p-doped GaAs. https://doi.org/10.1103/physrevb.73.081302

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