Parametric seeding of a microresonator optical frequency comb

TL;DR

This paper demonstrates that parametric seeding using electro-optic modulation can precisely control the spectrum of microresonator frequency combs, achieving record stability and generating strictly equidistant combs.

Contribution

It introduces a method to control microcomb spectra and subcombs via parametric seeding, leading to improved stability and spectral uniformity.

Findings

Record absolute line-spacing stability of 1.6×10⁻¹³ at 1 s.

Parametric seeding replicates pump-sideband spacing across the spectrum.

Generation of strictly equidistant microcomb spectrum.

Abstract

We have investigated parametric seeding of a microresonator frequency comb (microcomb) by way of a pump laser with two electro-optic-modulation sidebands. We show that the pump-sideband spacing is precisely replicated throughout the microcomb's optical spectrum, and we demonstrate a record absolute line-spacing stability for microcombs of $1.6\times10^{-13}$ at 1 s. The spectrum of a parametric comb is complex, and often non-equidistant subcombs are observed. Our results demonstrate that parametric seeding can not only control the subcombs, but can lead to the generation of a strictly equidistant microcomb spectrum.