All-Polarization-Maintaining, Mode-Locked 488 nm Picosecond Laser

In this letter, we report a 488 nm blue picosecond pulse generation by frequency doubling of a homemade 977 nm watt-level picosecond all polarization maintaining mode-locked fiber laser. Based on a SESAM passively mode-locked Yb-doped fiber linear cavity configuration, the 977 nm picosecond seed laser shows a 977.84 nm central wavelength, 0.13 nm spectral width, 12.94 ps pulse duration, 76.09 MHz repetition rate, and 5.12 mW average power, respectively. The average power is further scaled up to 2.06 W by adopting an all-fiber MOPA structure, and the pulse duration and spectral width are slightly broadened to 16.84 ps and 0.24 nm, respectively. Furthermore, a 147.40 mW blue picosecond pulsed laser with a 488.92 nm central wavelength and 0.17 nm linewidth is successfully achieved by frequency doubling in a MgO2:PPLN crystal. Such compact, high-power, and narrow-linewidth picosecond blue laser is a promising candidate for high-resolution imaging, underwater detection and material processing, etc.

Automated summary

In this study, a 488 nm blue picosecond pulse was generated by frequency doubling a homemade 977 nm picosecond fiber laser. The original laser had a 977.84 nm central wavelength, 0.13 nm spectral width, 12.94 ps pulse duration, 76.09 MHz repetition rate, and 5.12 mW average power. After scaling up the power to 2.06 W, the pulse duration and spectral width slightly increased to 16.84 ps and 0.24 nm, respectively. The blue picosecond laser achieved a central wavelength of 488.92 nm and a linewidth of 0.17 nm. This compact and high-power laser has potential applications in high-resolution imaging, underwater detection, and material processing.