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arXiv · 1012.4745

Gate-activated photoresponse in a graphene p-n junction

M. C. Lemme·F. H. L. Koppens·A. L. Falk·M. S. Rudner·H. Park·L. S. Levitov·C. M. Marcus
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Abstract

We study photodetection in graphene near a local electrostatic gate, which enables active control of the potential landscape and carrier polarity. We find that a strong photoresponse only appears when and where a p-n junction is formed, allowing on-off control of photodetection. Photocurrents generated near p-n junctions do not require biasing and can be realized using submicron gates. Locally modulated photoresponse enables a new range of applications for graphene-based photodetectors including, for example, pixilated infrared imaging with control of response on subwavelength dimensions.

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M. C. Lemme, F. H. L. Koppens, A. L. Falk, M. S. Rudner, H. Park, L. S. Levitov, C. M. Marcus. 2011-09-16. Gate-activated photoresponse in a graphene p-n junction. https://doi.org/10.1021/nl2019068

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