Fiber-integrated frequency-doubling of a picosecond Raman laser to 560 nm

Area of Science:

• Photonics
• Laser Physics
• Microscopy

Background:

• Fiber lasers offer robust and compact solutions for various applications.
• Picosecond pulsed lasers are crucial for high-resolution imaging and material processing.
• Second harmonic generation is a key technique for generating shorter wavelengths from existing laser sources.

Purpose of the Study:

• To develop a fiber-integrated picosecond laser source at 560 nm.
• To achieve high average power and excellent beam quality for microscopy.
• To utilize Raman fiber laser technology for efficient wavelength conversion.

Main Methods:

• A picosecond ytterbium master oscillator power fiber amplifier (MOPA) was used to pulse-pump a Raman amplifier.
• The Raman amplifier was seeded by a continuous wave distributed feedback laser diode at 1120 nm.
• Frequency doubling was achieved using a fiber-coupled periodically-poled lithium niobate (PPLN) crystal.

Main Results:

• A fiber-integrated picosecond source at 560 nm was successfully developed.
• The source achieved 450 mW of average power with a pulse duration of 150 ps at 47.5 MHz.
• A near diffraction-limited beam quality (M² = 1.02) was obtained.

Conclusions:

• The developed 560 nm picosecond fiber laser source demonstrates high performance.
• The excellent beam quality makes it suitable for super-resolution microscopy.
• This work showcases the potential of integrated fiber laser systems for advanced optical applications.