High power Yb-Raman combined nonlinear fiber amplifier

Area of Science:

• * Photonics and Laser Technology
• * Nonlinear Optics
• * Fiber Optics

Background:

• * High-power fiber lasers are crucial for various scientific and industrial applications.
• * Combining Ytterbium (Yb) gain and Raman amplification offers a pathway to enhanced power scaling.
• * Dual-wavelength fiber lasers provide versatile seed sources for complex amplification schemes.

Purpose of the Study:

• * To demonstrate a novel Ytterbium-Raman combined nonlinear fiber amplifier.
• * To achieve high-power output at 1120 nm using a dual-wavelength seed laser.
• * To numerically analyze and experimentally validate the amplifier's performance.

Main Methods:

• * Utilizing a 30 W dual-wavelength Ytterbium-doped fiber laser (1070 nm and 1120 nm) as the seed source.
• * Employing a 45-meter-long Ytterbium-doped fiber as the gain medium for power scaling and Raman amplification.
• * Conducting numerical simulations incorporating both Ytterbium and Raman gain mechanisms.

Main Results:

• * Achieved a record output power of 732 W at 1120 nm with 890 W pump power.
• * Demonstrated simultaneous power scaling of the 1070 nm laser and Raman amplification of the 1120 nm laser.
• * Numerical results showed good agreement with experimental observations.

Conclusions:

• * The developed Ytterbium-Raman combined amplifier is highly effective for high-power laser generation.
• * The amplifier design enables efficient simultaneous amplification across different mechanisms.
• * The system is suitable for amplifying lasers in the 1100-1150 nm wavelength range.