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arXiv · 1908.10799

Uni-traveling-carrier photodetector with high-contrast grating focusing-reflection mirrors

Qingtao Chen·Wenjing Fang·Yongqing Huang·Xiaofeng Duan·Kai Liu·Mohammad S. Sharawi·Xiaomin Ren
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Abstract

A novel uni-traveling-carrier photodetector (UTC-PD) structure with an integrated focusing-reflection (FR) mirror realized by a non-periodic concentric circular high-contrast grating (NP-CC-HCG), referred to as FR-UTC-PD, is proposed to enhance responsivity in conventional UTC-PDs. The FR-UTC-PD allows improving the responsivity by 36.5% at a 1.55-um wavelength as compared to a UTC-PD without integrated an FR mirror with 84.59% reflectivity. For 40-um-diameter PDs, the obtained 3-dB bandwidths are unaltered with values of 18 GHz at -3.0 V bias voltage. The radio-frequency (RF) output power and photocurrent are -1.77 dBm and 17.56 mA, respectively, at 10 GHz and the -6.0 V bias voltage.

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Qingtao Chen, Wenjing Fang, Yongqing Huang, Xiaofeng Duan, Kai Liu, Mohammad S. Sharawi, Xiaomin Ren. 2019-10-27. Uni-traveling-carrier photodetector with high-contrast grating focusing-reflection mirrors. https://doi.org/10.7567/1882-0786%2Fab5b4a

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