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Waveguide-integrated twisted bilayer graphene photodetectors.

ABSTRACT: Graphene photodetectors have exhibited high bandwidth and capability of being integrated with silicon photonics (SiPh), holding promise for future optical communication devices. However, they usually suffer from a low photoresponsivity due to weak optical absorption. In this work, we have implemented SiPh-integrated twisted bilayer graphene (tBLG) detectors and reported a responsivity of 0.65 A W^-1 for telecom wavelength 1,550 nm. The high responsivity enables a 3-dB bandwidth of >65 GHz and a high data stream rate of 50 Gbit s^-1. Such high responsivity is attributed to the enhanced optical absorption, which is facilitated by van Hove singularities in the band structure of high-mobility tBLG with 4.1^o twist angle. The uniform performance of the fabricated photodetector arrays demonstrates a fascinating prospect of large-area tBLG as a material candidate for heterogeneous integration with SiPh.

SUBMITTER: Wu Q

PROVIDER: S-EPMC11063206 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature

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Waveguide-integrated twisted bilayer graphene photodetectors.

Wu Qinci Q Qian Jun J Wang Yuechen Y Xing Luwen L Wei Ziyi Z Gao Xin X Li Yurui Y Liu Zhongfan Z Liu Hongtao H Shu Haowen H Yin Jianbo J Wang Xingjun X Peng Hailin H

Nature communications 20240501 1

Graphene photodetectors have exhibited high bandwidth and capability of being integrated with silicon photonics (SiPh), holding promise for future optical communication devices. However, they usually suffer from a low photoresponsivity due to weak optical absorption. In this work, we have implemented SiPh-integrated twisted bilayer graphene (tBLG) detectors and reported a responsivity of 0.65 A W<sup>-1</sup> for telecom wavelength 1,550 nm. The high responsivity enables a 3-dB bandwidth of >65 ...[more]

PMID: 38693107

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