Nanometric dual-comb ranging using photon-level microcavity solitons
Abstract
Absolute distance measurement with low return power, fast measurement speed, high precision, and immunity to intensity fluctuations is highly demanded in nanotechnology. However, achieving all these objectives simultaneously remains a significant challenge for miniaturized systems. Here, we demonstrate dual-comb ranging (DCR) that encompasses all these capabilities by using counter-propagating (CP) solitons generated in an integrated SiN microresonator. We derive equations linking the DCR precision with comb line powers, revealing the advantage of microcomb's large line spacing in precise ranging. Leveraging the advantage, our system reaches 1-nm-precision and measures nm-scale vibration at frequencies up to 0.9 MHz. We also show that precise DCR is possible even in the presence of strong intensity noise and loss, using a mean received photon number as low as 5.510 per pulse. Our work establishes an optimization principle for dual-comb systems and bridges high performance ranging with foundry-manufactured photonic chips.
Keywords
Cite
@article{arxiv.2408.05739,
title = {Nanometric dual-comb ranging using photon-level microcavity solitons},
author = {Zihao Wang and Yifei Wang and Baoqi Shi and Wei Sun and Changxi Yang and Junqiu Liu and Chengying Bao},
journal= {arXiv preprint arXiv:2408.05739},
year = {2025}
}