Photonic timing-engineered solitons for dual-microcomb metrology

TL;DR

This paper introduces a novel method called dynamical soliton trapping for microcombs, enabling precise timing control and high-precision ranging in integrated photonic systems, surpassing previous technologies in speed and accuracy.

Contribution

The paper presents a new timing-engineering technique for microcavity solitons using auxiliary laser injection, allowing fast, precise control of soliton timing for advanced metrology applications.

Findings

Achieved a soliton slew rate of 31.3 ps/μs, over 100 times faster than previous systems.

Demonstrated picometer-scale absolute ranging precision with a single integrated device.

Enabled both single-pixel and parallel ranging using phase retrieval from beat spectra.

Abstract

Dissipative microcavity solitons offer a route to integrate comb-based metrology systems on photonic chips. However, integrated solitons generally lack agile control of comb parameters, particularly pulse timing control, hindering their application in quantum-limited metrology. Here we introduce dynamical soliton trapping to enable optically timing-engineered microcombs (OTEM). By injecting an auxiliary laser to anchor one of the microcomb lines, we create a potential well to trap and steer the soliton. Thus, soliton timing can be engineered by phase modulating the injected laser. Theory and measurement reveal the fast response bandwidth of the OTEM, which enabled a soliton slew rate of 31.3 ps/$\mu$s, surpassing existing time-programmable fiber laser combs by more than two orders of magnitude. Leveraging the timing scan, we used a single OTEM for single-pixel and parallel ranging by retrieving the phase of the multi-heterodyne beat spectrum. Picometer-scale ranging precision was achieved, establishing new record for optical absolute ranging. Our work can transform timing-engineering of microcavity solitons and endow integrated dual-microcomb metrology systems with enhanced precision.