Dual-microcomb generation in a synchronously-driven waveguide ring resonator

TL;DR

This paper demonstrates the first experimental dual-microcomb generation in a single resonator using synchronous pulsed pumping, enabling new applications in spectroscopy and imaging.

Contribution

It introduces a novel method of dual-microcomb generation via synchronous pulsed driving of a single microresonator, utilizing polarization modes and birefringence.

Findings

Successful generation of two coherent Kerr soliton combs on orthogonal polarization modes.

Different repetition rates achieved due to resonator birefringence.

Proof-of-concept spectroscopic measurements using the dual-microcomb source.

Abstract

Microcombs -- optical frequency combs generated in coherently-driven nonlinear microresonators -- have attracted significant attention over the last decade. The ability to generate two such combs in a single resonator device has in particular enabled a host of applications from spectroscopy to imaging. Concurrently, novel comb generation techniques such as synchronous pulsed driving have been developed to enhance the efficiency and flexibility of microcomb generation. Here we report on the first experimental demonstration of dual-microcomb generation via synchronous pulsed pumping of a single microresonator. Specifically, we use two electro-optically generated pulse trains derived from a common continuous wave laser to simultaneously drive two orthogonal polarization modes of an integrated silica ring resonator, observing the generation of coherent dissipative Kerr cavity soliton combs on both polarization axes. Thanks to the resonator birefringence, the two soliton combs are associated with different repetition rates, thus realizing a dual-microcomb source. To illustrate the source's application potential, we demonstrate proof-of-concept spectroscopic measurements.