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arXiv · 2103.10557

Radio frequency spectrum analyzer with a 5 THz bandwidth based on nonlinear optics in a CMOS compatible high-index doped silica waveguide

Yuhua Li·Zhe Kang·Kun Zhu·Shiqi Ai·Xiang Wang·Roy R. Davidson·Yan Wu·Roberto Morandotti·Brent E. Little·David J. Moss·Sai Tak Chu
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Abstract

We report an all-optical radio-frequency (RF) spectrum analyzer with a bandwidth greater than 5 terahertz (THz), based on a 50-cm long spiral waveguide in a CMOS-compatible high-index doped silica platform. By carefully mapping out the dispersion profile of the waveguides for different thicknesses, we identify the optimal design to achieve near zero dispersion in the C-band. To demonstrate the capability of the RF spectrum analyzer, we measure the optical output of a femtosecond fiber laser with an ultrafast optical RF spectrum in the terahertz regime.

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Yuhua Li, Zhe Kang, Kun Zhu, Shiqi Ai, Xiang Wang, Roy R. Davidson, Yan Wu, Roberto Morandotti, Brent E. Little, David J. Moss, Sai Tak Chu. 2021-03-18. Radio frequency spectrum analyzer with a 5 THz bandwidth based on nonlinear optics in a CMOS compatible high-index doped silica waveguide. https://doi.org/10.1364/ol.420716

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