Optical Kerr soliton crystal microcomb source for RF photonic fractional differentiation

Mengxi Tan; Xingyuan Xu; Bill Corcoran; Jiayang Wu; Andreas Boes; Thach G. Nguyen; Sai T. Chu; Brent E. Little; Roberto Morandotti; Arnan Mitchell; David J. Moss

doi:10.1109/tcsii.2020.2965158

arXiv · 2001.03420

Optical Kerr soliton crystal microcomb source for RF photonic fractional differentiation

Mengxi Tan·Xingyuan Xu·Bill Corcoran·Jiayang Wu·Andreas Boes·Thach G. Nguyen·Sai T. Chu·Brent E. Little·Roberto Morandotti·Arnan Mitchell·David J. Moss

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Abstract

We report a photonic radio frequency (RF) fractional differentiator based on an integrated Kerr micro-comb source. The micro-comb source has a free spectral range (FSR) of 49 GHz, generating a large number of comb lines that serve as a high-performance multi-wavelength source for the differentiator. By programming and shaping the comb lines according to calculated tap weights, arbitrary fractional orders ranging from 0.15 to 0.90 are achieved over a broad RF operation bandwidth of 15.49 GHz. We experimentally characterize the frequency-domain RF amplitude and phase responses as well as the temporal responses with a Gaussian pulse input. The experimental results show good agreement with theory, confirming the effectiveness of our approach towards high-performance fractional differentiators featuring broad processing bandwidth, high reconfigurability, and potentially greatly reduced size and cost.

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Mengxi Tan, Xingyuan Xu, Bill Corcoran, Jiayang Wu, Andreas Boes, Thach G. Nguyen, Sai T. Chu, Brent E. Little, Roberto Morandotti, Arnan Mitchell, David J. Moss. 2020-01-08. Optical Kerr soliton crystal microcomb source for RF photonic fractional differentiation. https://doi.org/10.1109/tcsii.2020.2965158

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