Observation of operation states and wavelength-switching in spatiotemporal mode-locked lasers

Abstract

The construction and investigation of spatiotemporal mode-locked (STML) lasers offer us an opportunity to comprehend and analyze exceedingly intricate high-dimensional nonlinear physical phenomena that underlie diverse behaviors. While the exploration of coherent mode-locking, such as multimode solitons, has been progressing in depth, there remains a dearth of understanding regarding random pulses or extreme events within STML lasers. In this study, an STML laser was constructed and implemented with two operating regimes. The laser demonstrated mutual switching between noise-like pulses and dissipative soliton states, accompanied by corresponding changes in the output spectrum. The transition of the laser's output spectrum from a single wavelength to a synchronous dual-wavelength at noise-like pulses operation was observed for the first time, as far as we all know. These findings contribute to a deeper understanding of spatiotemporal mode-locked lasers.