A Novel Approach to Interface High-Q Fabry-P\'erot Resonators with Photonic Circuits
Abstract
The unique benefits of Fabry-P\'erot resonators as frequency-stable reference cavities and as an efficient interface between atoms and photons make them an indispensable resource for emerging photonic technologies. To bring these performance benefits to next-generation communications, computation, and timekeeping systems, it will be necessary to develop strategies to integrate compact Fabry-P\'erot resonators with photonic integrated circuits. In this paper, we demonstrate a novel reflection cancellation circuit that utilizes a numerically optimized multi-port polarization-splitting grating coupler to efficiently interface high-finesse Fabry-P\'erot resonators with a silicon photonic circuit. This circuit interface produces spatial separation of the incident and reflected waves, as required for on-chip Pound-Drever-Hall frequency locking, while also suppressing unwanted back reflections from the Fabry-P\'erot resonator. Using inverse design principles, we design and fabricate a polarization-splitting grating coupler that achieves 55% coupling efficiency. This design realizes an insertion loss of 5.8 dB for the circuit interface and more than 9 dB of back reflection suppression, and we demonstrate the versatility of this system by using it to interface several reflective off-chip devices.
Keywords
Cite
@article{arxiv.2310.12332,
title = {A Novel Approach to Interface High-Q Fabry-P\'erot Resonators with Photonic Circuits},
author = {Haotian Cheng and Naijun Jin and Zhaowei Dai and Chao Xiang and Joel Guo and Yishu Zhou and Scott A. Diddams and Franklyn Quinlan and John Bowers and Owen Miller and Peter Rakich},
journal= {arXiv preprint arXiv:2310.12332},
year = {2023}
}