Towards 'smart lasers': self-optimisation of an ultrafast pulse source using a genetic algorithm

TL;DR

This paper demonstrates the use of a genetic algorithm to automatically optimize and stabilize ultrafast pulse generation in a fibre laser, advancing towards self-optimizing 'smart' laser systems.

Contribution

It introduces a genetic algorithm-based method for fully automating the tuning of a complex ultrafast laser system, achieving stable single-pulse mode-locking.

Findings

Stable ultrashort pulses achieved repeatedly

Automated system turn-on process implemented

Optimization guided by a compound fitness function

Abstract

Short-pulse fibre lasers are a complex dynamical system possessing a broad space of operating states that can be accessed through control of cavity parameters. Determination of target regimes is a multi-parameter global optimisation problem. Here, we report the implementation of a genetic algorithm to intelligently locate optimum parameters for stable single-pulse mode-locking in a Figure-8 fibre laser, and fully automate the system turn-on procedure. Stable ultrashort pulses are repeatably achieved by employing a compound fitness function that monitors both temporal and spectral output properties of the laser. Our method of encoding photonics expertise into an algorithm and applying machine-learning principles paves the way to self-optimising `smart' optical technologies.