Dissipative Kerr Soliton Self-Balancing from Kerr-Induced Synchronization

TL;DR

This paper demonstrates how Kerr-induced synchronization enables a self-balancing effect in dissipative Kerr solitons, leading to increased dispersive wave radiation and improved carrier-envelope offset detection in integrated microcombs.

Contribution

It introduces a novel self-balancing mechanism in DKS microcombs via Kerr-induced synchronization, enhancing comb stability and detection capabilities.

Findings

Self-balancing alters DKS energy distribution.

22 dB increase in comb teeth at 780 nm observed.

Enhanced dispersive wave radiation improves offset detection.

Abstract

Integrated frequency comb sources are a key enabling technology for frequency metrology applications. Their on-chip integration promises to bring metrology capacity outside of the lab, particularly since they can operate at low continuous-wave pump laser power in the dissipative Kerr soliton (DKS) regime. Yet, such small foot-print and low power comes at a cost: higher noise and overall lower comb power. In particular, this translates to highly challenging detection and locking of the carrier-envelope offset, necessary for complete stabilization of the comb. Recently, Kerr-induced synchronization (KIS) of a DKS to a reference laser has been demonstrated as a tool for passive all-optical stabilization of DKS microcombs, with fundamental modification to the DKS and microcomb properties. Here, we demonstrate that the combination of additional power from the reference laser (now part of the DKS) and the KIS phase locking that pins the repetition rate together fundamentally alter the DKS, forcing an energy redistribution to maintain its center of mass. We demonstrate this self-balancing effect theoretically, which in a pure quadratic dispersion resonator leads to reference-dependent recoil. With higher-order dispersion through which the DKS yields phase-matched dispersive waves (DWs), we demonstrate that self-balancing increases the DW radiation, experimentally showing a 22 dB increase of comb teeth at 780 nm in an octave-spanning microcomb for efficient deployable carrier-envelope offset detection.