Zheyu Fang, Zheng Liu, Yumin Wang, Pulickel M Ajayan, Peter Nordlander, Naomi J Halas
Department of Electrical and Computer Engineering, Laboratory for Nanophotonics, Rice University, Houston, Texas 77005, United States. zf4@rice.edu
Nano letters 2012 Jul 11Nanoscale antennas sandwiched between two graphene monolayers yield a photodetector that efficiently converts visible and near-infrared photons into electrons with an 800% enhancement of the photocurrent relative to the antennaless graphene device. The antenna contributes to the photocurrent in two ways: by the transfer of hot electrons generated in the antenna structure upon plasmon decay, as well as by direct plasmon-enhanced excitation of intrinsic graphene electrons due to the antenna near field. This results in a graphene-based photodetector achieving up to 20% internal quantum efficiency in the visible and near-infrared regions of the spectrum. This device can serve as a model for merging the light-harvesting characteristics of optical frequency antennas with the highly attractive transport properties of graphene in new optoelectronic devices.
Zheyu Fang, Zheng Liu, Yumin Wang, Pulickel M Ajayan, Peter Nordlander, Naomi J Halas. Graphene-antenna sandwich photodetector. Nano letters. 2012 Jul 11;12(7):3808-13
PMID: 22703522
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