Adaptive genetic algorithm-based 2 μm intelligent mode-locked fiber laser

Abstract

The emission wavelength of an ultrafast laser generated by thulium (Tm)-doped fiber laser (TDFL) ranges from 1.7 to 2.1 μm, covering the water-absorbing band and atmospheric transmission window. In this study, an intelligent Tm-doped mode-locked fiber laser was experimentally demonstrated by combining a genetic algorithm (GA) with an adaptive mutation rate and a nonlinear polarization rotation mode-locked fiber oscillator. A closed-loop feedback system was set up in the experiment, including an oscilloscope, a laptop computer, an electric polarization controller, and a mode-locked fiber oscillator. Based on the aforementioned intelligent design of manual-operation-free, a stable femtosecond level noise-like-mode-locked pulse with an output power of 57.7 mW and a central wavelength of 1973 nm was automatically generated. The evolutionary dynamics of the different parameter structures of the GA-controlled ultrafast TDFL with varying mutation rates were also investigated. This study will pave the way for generating robust ultrafast lasers in the short-wave infrared region.