Temporal solitons in active optical resonators

TL;DR

This paper explores the generation and control of temporal solitons in active optical resonators, highlighting their potential for advanced laser and photonic applications, especially in quantum cascade lasers and hybrid systems.

Contribution

It provides a comprehensive overview of active resonator architectures supporting solitons, emphasizing their advantages over conventional lasers and proposing future research directions.

Findings

Active resonators can sustain stable temporal solitons.

Hybrid driving schemes enhance soliton control and versatility.

Quantum cascade lasers are promising platforms for soliton technology.

Abstract

Solitons, as coherent structures that maintain their shape while traveling at constant velocity, are ubiquitous across various branches of physics, from fluid dynamics to quantum fields. However, it is within the realm of optics where solitons have not only served as a primary testbed for understanding solitary wave phenomena but have also transitioned into applications ranging from telecommunications to metrology. In the optical domain, temporal solitons are localized light pulses, self-reinforcing via a delicate balance between nonlinearity and dispersion. Among the many systems hosting temporal solitons, active optical resonators stand out due to their inherent gain medium, enabling to actively sustain solitons. Unlike conventional modelocked lasers, active resonators offer a richer landscape for soliton dynamics through hybrid driving schemes, such as coupling to passive cavities or under external optical injection, affording them unparalleled control and versatility. We discuss key advantages of these systems, with a particular focus on quantum cascade lasers as a promising soliton technology within the class of active resonators. By exploring diverse architectures from traditional Fabry-Perot cavities to racetrack devices operated under external injection, we present the current state-of-the-art and future directions for soliton-based sources in the realm of semiconductor lasers and hybrid integrated photonic systems.