Visible-Wavelength All-Fiber Mode-Locked Vortex Laser

We report, to the best of our knowledge, the first visible-wavelength all-fiber passively mode-locked vortex laser by a figure-9 cavity in combination with similar to 635 nm mode selective coupler, which can deliver picosecond optical vortex pulses with topological charges of OAM(+/- 1). The mode-locked vortex laser emits stable rectangular pulses with pulse duration tunable range from 85 to 510 ps and a 0.16-nm narrow linewidth at 634.36 nm. The maximum output power of the vortex laser reaches 1.3 mW with a high purity similar to 97.2%. This work demonstrated the generation of picosecond pulsed vortex in visible passively mode-locked fiber laser, showing their potential for applications in particle trapping, optical tweezers, and high-resolution microscopy.

Automated summary

We report the first visible-wavelength all-fiber passively mode-locked vortex laser, capable of delivering picosecond optical vortex pulses with adjustable pulse duration and narrow linewidth. This study also demonstrates the potential applications of this technology in particle trapping, optical tweezers, and high-resolution microscopy.