Ultrafast optical ranging using microresonator soliton frequency combs

TLDR

LIDAR is essential across science and industry, and while optical frequency combs promise fast, accurate ranging, existing comb‑based systems lack the compactness, robustness, and cost‑efficiency required for high‑volume applications such as drone navigation and autonomous driving. This work demonstrates that integrated dissipative Kerr‑soliton comb sources enable chip‑scale LIDAR systems delivering sub‑wavelength accuracy and unprecedented acquisition speed, paving the way for wafer‑scale mass production. The authors employ a pair of free‑running DKS combs, each providing over 100 carriers, to perform massively parallel synthetic‑wavelength interferometry for dual‑comb distance measurement. They achieve dual‑comb ranging with Allan deviations as low as 12 nm at 14 µs averaging, ultrafast measurement rates up to 100 MHz, and successfully track air‑gun projectiles at 150 m/s, indicating the technique’s viability for compact, high‑speed LIDAR in mass‑produced systems.

Abstract

Light detection and ranging (LIDAR) is critical to many fields in science and industry. Over the last decade, optical frequency combs were shown to offer unique advantages in optical ranging, in particular when it comes to fast distance acquisition with high accuracy. However, current comb-based concepts are not suited for emerging high-volume applications such as drone navigation or autonomous driving. These applications critically rely on LIDAR systems that are not only accurate and fast, but also compact, robust, and amenable to cost-efficient mass-production. Here we show that integrated dissipative Kerr-soliton (DKS) comb sources provide a route to chip-scale LIDAR systems that combine sub-wavelength accuracy and unprecedented acquisition speed with the opportunity to exploit advanced photonic integration concepts for wafer-scale mass production. In our experiments, we use a pair of free-running DKS combs, each providing more than 100 carriers for massively parallel synthetic-wavelength interferometry. We demonstrate dual-comb distance measurements with record-low Allan deviations down to 12 nm at averaging times of 14 $μ$s as well as ultrafast ranging at unprecedented measurement rates of up to 100 MHz. We prove the viability of our technique by sampling the naturally scattering surface of air-gun projectiles flying at 150 m/s (Mach 0.47). Combining integrated dual-comb LIDAR engines with chip-scale nanophotonic phased arrays, the approach could allow widespread use of compact ultrafast ranging systems in emerging mass applications.