Soliton Formation in Whispering-Gallery-Mode Resonators via Input Phase Modulation

TL;DR

This paper introduces a phase modulation technique to reliably generate solitons in whispering-gallery-mode resonators, enhancing control over frequency combs and enabling ultra-short pulse creation on a chip.

Contribution

It demonstrates a novel input phase modulation method for deterministic soliton formation in WGM resonators, supported by numerical simulations of the Lugiato-Lefever equation.

Findings

Phase modulation at the resonator's free-spectral-range facilitates soliton formation.

Solitons are stable and can be maintained after modulation is turned off.

Parametric seeding offers a new control mechanism for frequency combs.

Abstract

We propose a method for soliton formation in whispering-gallery-mode (WGM) resonators through input phase modulation. Our numerical simulations of a variant of the Lugiato-Lefever equation suggest that modulating the input phase at a frequency equal to the resonator free-spectral-range and at modest modulation depths provides a deterministic route towards soliton formation in WGM resonators without undergoing a chaotic phase. We show that the generated solitonic state is sustained when the modulation is turned off adiabatically. Our results support parametric seeding as a powerful means of control, besides input pump power and pump-resonance detuning, over frequency comb generation in WGM resonators. Our findings also help pave the path towards ultra-short pulse formation on a chip.