The development of ultrafast laser pulse generation has revolutionized laser science, leading to significant advancements in various fields such as industrial applications, energy technologies, and life sciences. Fiber femtosecond oscillators, known for their compact design, exceptional performance, and cost-effectiveness, have emerged as a leading technology for femtosecond pulse generation.
Most visible fiber lasers currently utilize rare-earth-doped fluoride fibers, particularly Pr3+, as the effective gain medium. Significant progress has been made in developing wavelength-tunable, high-power, Q-switched, and mode-locked visible fiber lasers.
However, achieving femtosecond mode-locking in visible fiber lasers remains a challenging task due to the underdevelopment of ultrafast optics components at visible wavelengths, limited availability of high-performance visible modulators, and the normal dispersion encountered in visible fiber laser cavities.
Recent advancements have focused on femtosecond mode-locked fiber oscillators in the near-infrared using a phase-biased nonlinear amplifying loop mirror (PB-NALM). This innovation eliminates the need for long intracavity fibers to accumulate phase shifts, providing tuning flexibility and long-life operation while managing intracavity dispersion in a larger parameter space.
As a result, this innovation is expected to catalyze a breakthrough in direct femtosecond mode-locking of visible fiber lasers and propel fiber femtosecond oscillators into the visible band.
2024-03-28 00:00:04
Link from phys.org