Multi‐Soliton Microcomb Dispersive Interferometry Enabling Precise Distance Measurement

ABSTRACT Microcombs have demonstrated remarkable capabilities in precision measurement. While single‐soliton states possess excellent coherence, their low power conversion efficiency limits practical applications. Conversely, chaotic states achieve high efficiency but suffer from excessive noise. Multi‐soliton states address these constraints by offering high efficiency while preserving coherence. Here, we employ a multi‐soliton microcomb for dispersive interferometry ranging, extracting multiple weakly correlated temporal peaks from one spectrogram and utilizing them to improve measurement precision at the same averaging time. The microcomb pump is locked to the rubidium atomic transition, and the repetition rate is stabilized to the hydrogen maser. Experimental results show that the multi‐soliton dispersive interferometry measurements agree with the reference values within 360 nm. Compared to single‐soliton operation, the precision is enhanced approximately 2.5‐fold, reaching 80.6 nm at 4 s and 2.25 nm at 600 s averaging time. Furthermore, the multi‐soliton homodyne interferometry results fall within 13 nm of the reference values, achieving a precision of 736 pm at 4 s and 24.9 pm at 600 s, representing about 1.5‐times improvement relative to the single‐soliton case. We also present three‐dimensional imaging of static and dynamic targets. This work is expected to pave the way for multi‐soliton applications in diverse optical fields.