2020, Dynamic control of high-range photoresponsivity in graphene nanoribbon photodetector. Nanoscale Research Letters.

Dynamic control of high-range photoresponsivity in graphene nanoribbon photodetector( 2020, Nanoscale Research Letters)

Abstract:

Graphene has been demonstrated to be a promising material for optoelectronics and photodetection devices because of its ultra-broadband optical absorption and high carrier mobility. However, its integration with optoelectronic systems has been limited by the zero-bandgap and the lack of a gain mechanism. Herein, we demonstrate a novel photodetector based on the graphene nanoribbons (GRNs) with a sizable bandgap, and utilize trapping charge at the interface between SiO2 and light-doped silicon to obtain an ultrahigh gain of 22400. Our devices show an enhanced photoresponsivity (~800 AW-1) while the response speed is still fast (up to 10 ms). To the best of our knowledge, the value of high photoresponsivity is about two orders of magnitude compared with a previous graphene-based photodetector. The photodetector exhibits a wide-range tunability via source-drain bias and back gate voltage. Our work addresses key challenges for the photodetectors with limited photoresponsivity, and potentially provides the desired pathway towards practical application of graphene photodetectors which can be externally manipulated by the electric field and possess fast response time and high sensitivity.

Keywords: graphene nanoribbon，photodetector ，photoresponsivity

Link: https://nanoscalereslett.springeropen.com/articles/10.1186/s11671-020-03352-7