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arXiv · 1204.4371

Triggering and probing of phase-coherent spin packets by time-resolved spin transport across an Fe/GaAs Schottky barrier

L. R. Schreiber·C. Schwark·S. Richter·C. Weier·G. Güntherodt·C. Adelmann·C. J. Palmstrom·X. Lou·P. A. Crowell·B. Beschoten
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Abstract

Time-resolved electrical spin transport is used to generate and probe spin currents in GaAs electrically. We use high bandwidth current pulses to inject phase-coherent spin packets from Fe into n-GaAs. By means of time-resolved Faraday rotation we demonstrate that spins are injected with a clearly defined phase by the observation of multiple Larmor precession cycles. We furthermore show that spin precession of optically created spin packets in n-GaAs can be probed electrically by spin-polarized photo-current pulses. The injection and detection experiments are not direct reciprocals of each other. In particular, we find that interfacial spin accumulation generated by the photocurrent pulse plays a critical role in time-resolved electrical spin detection.

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L. R. Schreiber, C. Schwark, S. Richter, C. Weier, G. Güntherodt, C. Adelmann, C. J. Palmstrom, X. Lou, P. A. Crowell, B. Beschoten. 2012-04-19. Triggering and probing of phase-coherent spin packets by time-resolved spin transport across an Fe/GaAs Schottky barrier. https://arxiv.org/abs/1204.4371

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