Real‐Time Comprehensive Control over Soliton Molecules Enabled By Physics‐Inspired Searching

Abstract

AbstractSoliton molecules (SMs), which represent bound aggregations of sub‐solitons, have inherent multi‐dimensional properties, thereby giving them substantial potential for use in optical communications and optical data storage. However, releasing this potential requires the ability to control SMs over these multiple dimensions to allow valid information to be modulated onto these dimensions. Here, a real‐time feedback scheme is proposed that is governed using a specifically designed physics‐inspired searching strategy and provides comprehensive control of the SM's multi‐dimensional properties. This technique can be used to manipulate the inter‐soliton separations and the relative intensities of the SMs within a basic nonlinear‐polarization‐evolution‐based mode‐locked fiber laser (MLFLs). A wide tuning range for the inter‐soliton separation from 2 to 58 ps is achieved and seamless tuning with ultra‐high precision of 0.05 ps is also demonstrated. The relative intensities between solitons can also be controlled separately and a 2D joint regulation procedure is performed. Furthermore, real‐time transmission over a 30‐km‐long single‐mode fiber is demonstrated and spectral period doubling of the SMs is captured, thus providing further confirmation of the validity of the proposed comprehensive control method.