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arXiv · 1005.1796

Spatially resolved ultrafast transport current in GaAs photoswitches

L. Prechtel·S. Manus·D. Schuh·W. Wegscheider·A. W. Holleitner
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Abstract

We apply a pump- and probe-scheme to coplanar stripline circuits to investigate the photocurrent response of GaAs photoswitches in time and space. We find a displacement current pulse, as has been reported earlier. A time-delayed second pulse is interpreted by a transport current. A time-of-flight analysis allows us to determine the velocity of the photogenerated charge carriers in the transport current. It exceeds the Fermi and the single-particle quantum velocities. This suggests that the excitation of a collective electron-hole plasma and not single charge-carriers dominates the ultrafast transport current in GaAs photoswitches.

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L. Prechtel, S. Manus, D. Schuh, W. Wegscheider, A. W. Holleitner. 2010-05-11. Spatially resolved ultrafast transport current in GaAs photoswitches. https://doi.org/10.1063/1.3458819

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