Enhancing laser brightness in a rare-earth-free system

Abstract

Abstract Multimode fibers, which support a complex mix of spatial and temporal nonlinear phenomena, have recently reemerged as a viable experimental platform for studying intricate physical processes. Additionally, their high-power handling abilities enable them widely used in applications beyond telecommunications. Within this research paper, we conducted a comprehensive theoretical analysis of the nonlinear dynamics involved in the process of Kerr effect-enhanced beam cleanup during stimulated Raman scattering in multimode graded-index fibers. Leveraging this nonlinear dynamic, and spectral synthesis technology to enhance the pump brightness, high-brightness radiation with previously unprecedented power is experimentally generated in a rare-earth-free and purely passive fiber-based system. This experimental achievement serves as compelling evidence for the immense capability of the localized Kerr effect-enhanced Raman beam cleaning as a highly efficient brightness converter. And this extraordinary contribution unveils invaluable and revolutionary insights that forge an entirely new frontier in the realm of laser design, delivering an unprecedented vantage point that transcends conventional boundaries. © The Author(s) 2023