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arXiv · 1402.1266

Photo-thermoelectric and photoelectric contributions to light detection in metal-graphene-metal photodetectors

T. J. Echtermeyer·P. S. Nene·M. Trushin·R. V. Gorbachev·A. L. Eiden·S. Milana·Z. Sun·J. Schliemann·E. Lidorikis·K. S. Novoselov·A. C. Ferrari
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Abstract

Graphene's high mobility and Fermi velocity, combined with its constant light absorption in the visible to far-infrared range, make it an ideal material to fabricate high-speed and ultra-broadband photodetectors. However, the precise mechanism of photodetection is still debated. Here, we report wavelength and polarization dependent measurements of metal-graphene-metal photodetectors. This allows us to quantify and control the relative contributions of both photo-thermo- and photoelectric effects, both contributing to the overall photoresponse. This paves the way for a more efficient photodetector design for ultra-fast operating speeds.

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T. J. Echtermeyer, P. S. Nene, M. Trushin, R. V. Gorbachev, A. L. Eiden, S. Milana, Z. Sun, J. Schliemann, E. Lidorikis, K. S. Novoselov, A. C. Ferrari. 2014-02-06. Photo-thermoelectric and photoelectric contributions to light detection in metal-graphene-metal photodetectors. https://doi.org/10.1021/nl5004762

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