SBS-managed high-peak-power nanosecond-pulse fiber-based master oscillator power amplifier

Area of Science:

• Optics and Photonics
• Laser Physics
• Materials Science

Background:

• Fiber lasers offer compact and efficient laser sources.
• High-power fiber lasers are limited by nonlinear effects like stimulated Brillouin scattering (SBS).
• Controlling laser output characteristics is crucial for specialized applications.

Purpose of the Study:

• To report a novel, compactly packaged Ytterbium (Yb)-doped fiber laser architecture.
• To overcome power limitations imposed by stimulated Brillouin scattering (SBS).
• To achieve high pulse energy and peak power with excellent spectral brightness.

Main Methods:

• Utilized a single-longitudinal-mode seeder with active pulse control.
• Employed a multistage amplifier chain incorporating a "folded" rod-type photonic crystal fiber.
• Managed SBS by phase modulating the seeder with a pseudo-random noise signal.

Main Results:

• Achieved pulse energy of approximately 2 mJ at a 10 kHz repetition rate.
• Obtained a peak power of approximately 1.5 MW.
• Generated pulses of ~1.55 ns duration with peak spectral brightness exceeding 20 kW cm⁻² sr⁻¹ Hz⁻¹.
• Demonstrated effective management of stimulated Brillouin scattering (SBS).

Conclusions:

• The developed laser architecture provides a compact and powerful solution for high-energy pulsed laser generation.
• The implemented SBS management technique is effective in enhancing laser output power.
• The laser system exhibits high spectral brightness, suitable for demanding applications in optics and photonics.