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arXiv · 1312.3737

High performance bilayer-graphene Terahertz detectors

Davide Spirito·Dominique Coquillat·Sergio L. De Bonis·Antonio Lombardo·Matteo Bruna·Andrea C. Ferrari·Vittorio Pellegrini·Alessandro Tredicucci·Wojciech Knap·Miriam S. Vitiello
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Abstract

We report bilayer-graphene field effect transistors operating as THz broadband photodetectors based on plasma-waves excitation. By employing wide-gate geometries or buried gate configurations, we achieve a responsivity $\sim 1.2V/W (1.3 mA/W)$ and a noise equivalent power $\sim 2\times 10^{-9} W/Hz^{-1/2}$ in the 0.29-0.38 THz range, in photovoltage and photocurrent mode. The potential of this technology for scalability to higher frequencies and the development of flexible devices makes our approach competitive for a future generation of THz detection systems.

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Davide Spirito, Dominique Coquillat, Sergio L. De Bonis, Antonio Lombardo, Matteo Bruna, Andrea C. Ferrari, Vittorio Pellegrini, Alessandro Tredicucci, Wojciech Knap, Miriam S. Vitiello. 2013-12-13. High performance bilayer-graphene Terahertz detectors. https://doi.org/10.1063/1.4864082

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