Optical-frequency measurements with a Kerr-microcomb and photonic-chip supercontinuum

TL;DR

This paper demonstrates a reliable method to generate and stabilize an octave-spanning Kerr microcomb on a chip, enabling high-precision optical frequency measurements and comparisons across the near-infrared spectrum.

Contribution

We introduce a simple, deterministic approach to produce and stabilize a Kerr microcomb with supercontinuum generation suitable for optical metrology.

Findings

Achieved an octave-spanning supercontinuum from 700 to 2100 nm.

Successfully stabilized the microcomb for precise optical frequency measurements.

Performed a microcomb-mediated comparison of ultrastable optical-reference cavities.

Abstract

Dissipative solitons formed in Kerr microresonators may enable chip-scale frequency combs for precision optical metrology. Here we explore the creation of an octave-spanning, 15-GHz repetition-rate microcomb suitable for both f-2f self-referencing and optical-frequency comparisons across the near infrared. This is achieved through a simple and reliable approach to deterministically generate, and subsequently frequency stabilize, soliton pulse trains in a silica-disk resonator. Efficient silicon-nitride waveguides provide a supercontinuum spanning 700 to 2100 nm, enabling both offset-frequency stabilization and optical-frequency measurements with >100 nW per mode. We demonstrate the stabilized comb by performing a microcomb-mediated comparison of two ultrastable optical-reference cavities.