High-power picosecond fiber amplifier based on nonlinear spectral compression

Area of Science:

• Optics and Photonics
• Laser Physics
• Materials Science

Background:

• Rare-earth-doped fiber lasers are crucial for generating high-energy ultrashort pulses.
• Achieving transform-limited pulses with high peak power is essential for nonlinear optical applications.
• Self-phase modulation is a key mechanism for pulse shaping and spectral broadening in optical fibers.

Purpose of the Study:

• To demonstrate the generation of nearly transform-limited 10-picosecond pulses using a rare-earth-doped fiber laser.
• To investigate the potential of self-phase modulation for spectral compression in a low-nonlinearity photonic crystal fiber.
• To explore the application of the generated high-power laser pulses for efficient second-harmonic generation.

Main Methods:

• Utilized an ytterbium-doped low nonlinearity photonic crystal fiber as the gain medium.
• Employed self-phase modulation to induce spectral compression, achieving nearly transform-limited pulse generation.
• Characterized the output laser pulses for duration, spectral properties, average power, and peak power.

Main Results:

• Successfully generated nearly transform-limited 10-picosecond pulses.
• Achieved an average output power of up to 97 W at a 47 MHz repetition rate.
• Obtained a peak power as high as 200 kW.
• Demonstrated efficient second-harmonic generation using the developed laser source.

Conclusions:

• Rare-earth-doped fiber lasers, combined with self-phase modulation, provide an effective route to high-power, ultrashort pulse generation.
• The demonstrated 200 kW peak power pulses are suitable for various nonlinear optical processes, including efficient second-harmonic generation.
• This work advances the capabilities of fiber laser technology for high-intensity applications.