Laser Cavity-Soliton Micro-Combs

TL;DR

This paper introduces laser cavity-soliton micro-combs, a highly efficient, background-free class of solitary waves in micro-cavities, enabling low-power, tunable frequency combs with potential for widespread practical applications.

Contribution

It demonstrates the generation of laser cavity-soliton micro-combs with significantly lower power requirements and tunable repetition rates, merging properties of cavity-solitons with micro-resonator physics.

Findings

50 nm wide soliton combs achieved

Power consumption an order of magnitude lower than existing methods

Repetition rate tunable over several megahertz

Abstract

The field of micro-cavity based frequency combs, or 'micro-combs'[1,2], has recently witnessed many fundamental breakthroughs[3-19] enabled by the discovery of temporal cavity-solitons, self-localised waves sustained by a background of radiation usually containing 95% of the total power[20]. Simple methods for their efficient generation and control are currently researched to finally establish micro-combs as out-of-the-lab widespread tools[21]. Here we demonstrate micro-comb laser cavity-solitons, an intrinsically highly-efficient, background free class of solitary waves. Laser cavity-solitons have underpinned key breakthroughs in semiconductor lasers[22,23] and photonic memories[24-26]. By merging their properties with the physics of both micro-resonators[1,2] and multi-mode systems[27], we provide a new paradigm for the generation and control of self-localised pulses in micro-cavities. We demonstrate 50 nm wide soliton combs induced with average powers one order of magnitude lower than those typically required by state-of-the-art approaches[26]. Furthermore, we can tune the repetition-rate to well over a megahertz with no-active feedback.