NOVEL FIBER-OPTIC COMPONENTS: Mode converter scales power in rectangular-core fiber amplifiers

摘要

In 2008, researchers at Lawrence Livermore National Laboratory (LLNL; Livermore, CA) analyzed the scalability of diffraction-limited fiber lasers, considering thermal, nonlinear, damage, pump coupling, and mode-field diameter (MFD) restrictions, and determined that fiber-laser amplifiers using conventional large-mode-area (LMA) and/or photonic-crystal (PC) fibers could output a maximum of around 36 kW with diffraction-limited beam quality. Many of those same researchers from LLNL have now proposed that rectangular-core fibers could extend single-aperture fiber-laser amplifier output to greater than 100 kW, and have developed a mode-converter system that will enable such scaling.