Observation of Arnold Tongues in Coupled Soliton Kerr Frequency Combs

TL;DR

This paper reports the experimental observation of Arnold tongues in coupled Kerr frequency combs, revealing synchronization regimes that enhance control over comb dynamics for various technological applications.

Contribution

It demonstrates the existence of Arnold tongues in coupled soliton Kerr frequency combs and validates findings with numerical simulations, expanding understanding of comb synchronization.

Findings

Observation of sub-harmonic, harmonic, and harmonic-ratio synchronization regimes.

Experimental and numerical agreement on Arnold tongue structures.

Potential applications in time/frequency metrology and optical communications.

Abstract

We demonstrate various regimes of synchronization in systems of two coupled cavity soliton-based Kerr frequency combs. We show sub-harmonic, harmonic and harmonic-ratio synchronization of coupled microresonators, and reveal their dynamics in the form of Arnold tongues, structures that are ubiquitous in nonlinear dynamical systems. Our experimental results are well corroborated by numerical simulations based on coupled Lugiato-Lefever equations. This study illustrates the newfound degree of flexibility in synchronizing Kerr combs across a wide range of comb spacings and could find applications in time and frequency metrology, spectroscopy, microwave photonics, optical communications, and astronomy.