Real-time collision dynamics of vector solitons in a fiber laser

Abstract

Particle-like structures of solitons, as a result of the balance between dispersion and nonlinearity, enable remarkable elastic and inelastic soliton collisions in many fields. Despite the experimental observation of temporal vector-soliton collisions in birefringent fibers, collision dynamics of vector solitons in fiber lasers have not been revealed before, to the best of our knowledge. Here, the real-time spectral evolutions of vector solitons during collisions in a dual-comb fiber laser, which generates vector solitons with slightly different repetition rates, are captured by a time-stretch dispersive Fourier transform technique. We record the whole process of vector-soliton collisions, including the formation of weak pulses induced by cross-polarization coupling, opposite central wavelength shifts of both vector solitons, distinct intensity redistribution and dissipative energy, and gradual recovery to initial states. Furthermore, extreme collisions with strong four-wave mixing sidebands are observed by virtue of coherent coupling between the orthogonal polarization components of vector solitons. Numerical simulations match well with the experimental observations. The experimental and numerical evidences of vector-soliton collision dynamics could give insight into the understanding of nonlinear dynamics in fiber lasers and other physical systems, as well as the improvement of laser performance for application in dual-comb spectroscopy.

Real‐Time Observation of the Formation of Dual‐Wavelength Mode Locking

“…[30,31] Similarly, real-time observation of the buildup and collision dynamics of asynchronous vector solitons were systematically investigated. [32,33] Despite these significant investigations on the dual-wavelength mode-locking fiber lasers, a fundamental question remains elusive: how does noise evolve to dual-wavelength mode-locking solitons? In particular, the formation of a single soliton refers to the universal behavior of many nonlinear systems featuring the scenario of 'survival of the strongest'.…”

“…[ 30,31 ] Similarly, real‐time observation of the buildup and collision dynamics of asynchronous vector solitons were systematically investigated. [ 32,33 ]…”

Characteristic extraction of soliton dynamics based on convolutional autoencoder neural network

“…PMLFLs are typical dissipative nonlinear systems with high noise sensitivity and rich physical mechanisms. Among them, soliton collisions [5,6] , soliton molecules [7,8] , and soliton explosions [9,10] have been extensively studied, both experimentally and theoretically. In recent years, as a universal modeling scheme of complex systems, deep learning has been widely used in the field of nonlinear dynamics, such as predicting pulse propagation dynamics [11,12] , characterizing ultrashort optical pulses [13] , predicting the dynamics in PMLFLs [14] , and modeling physically analytic soliton interactions [15,16] .…”

Real-Time Access to Collisions between a Two-Soliton Molecule and a Soliton Singlet in an Ultrafast Fiber Laser

“…Moreover, the field autocorrelation traces could be obtained by Fourier transform of the corresponding shot-to-shot DFT spectra to probe the internal evolutions of the soliton molecule and soliton triplet [28,29]. The powerful DFT technique has also been applied to revealing real-time dynamics of soliton collisions [30][31][32][33].…”