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Plasmonically induced perfect absorption in graphene/metal system.

ABSTRACT: The constructive interference of bright and dark plasmonic modes results in plasmon-induced absorption (PIA) effect. Here, we theoretically investigate PIA effect, which is realized by the constructive interference between a Fabry-Perot (F-P) resonance mode and a graphene quasi-guided mode. Numerical simulation reveals at least three advantages of our structure over previous ones. First, the extinction ratio can reach ~?99.999%, resulting in the ultra-high figure of merit* (FOM*) as high as 10⁶. Second, the intensity of this pronounced PIA effect can be optimized by adjusting the coupling distance. Third, the resonance frequency can be easily tunable by tuning the graphene Fermi level. This system may have potential applications in dynamically optical switching and biochemical sensing.

SUBMITTER: Hu C

PROVIDER: S-EPMC6713770 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Plasmonically induced perfect absorption in graphene/metal system.

Hu Cheng C Lin Qi Q Zhai Xiang X Wen Mengting M Wang Lingling L

Nanoscale research letters 20190828 1

The constructive interference of bright and dark plasmonic modes results in plasmon-induced absorption (PIA) effect. Here, we theoretically investigate PIA effect, which is realized by the constructive interference between a Fabry-Perot (F-P) resonance mode and a graphene quasi-guided mode. Numerical simulation reveals at least three advantages of our structure over previous ones. First, the extinction ratio can reach ~ 99.999%, resulting in the ultra-high figure of merit* (FOM*) as high as 10<s ...[more]

PMID: 31463727

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