Dual-mode microresonators as straightforward access to octave-spanning dissipative Kerr solitons

TL;DR

This paper introduces a novel dual-mode microresonator design enabling stable, octave-spanning dissipative Kerr solitons without auxiliary components, advancing compact, robust, and efficient frequency comb sources for various applications.

Contribution

The work presents a new microresonator scheme with two adjacent modes that stabilizes soliton formation and generates broad, stable frequency combs without extra lasers or RF components.

Findings

Achieved deterministic generation of 1.5-octave solitons near 200 THz.

Demonstrated ultra-wide soliton existence range up to 17 GHz.

Enabled multi-solitons and soliton crystals with high efficiency and tunability.

Abstract

The Kerr soliton frequency comb is a revolutionary compact ruler of coherent light that allows applications, from precision metrology to quantum information technology. The universal, reliable, and low-cost soliton microcomb source is key to these applications. In this work, we thoroughly present an innovative design strategy for realizing optical microresonators with two adjacent modes, separated by approximately 10 GHz, which stabilizes soliton formation without using additional auxiliary laser or RF components. We demonstrate the deterministic generation of the single-solitons that span 1.5-octaves, i.e., near 200 THz, via adiabatic pump wavelength tuning. The ultra-wide soliton existence ranges up to 17 GHz not only suggests the robustness of the system but will also extend the applications of soliton combs. Moreover, the proposed scheme is found to easily give rise to multi-solitons as well as the soliton crystals featuring enhanced repetition rate (2 and 3 THz) and conversion efficiency greater than 10%. We also show the effective thermal tuning of mode separation for stably accessing single-soliton. Our results are crucial for the chip-scale self-referenced frequency combs with a simplified configuration.