23  mJ high-power fiber CPA system using electro-optically controlled divided-pulse amplification.

Area of Science:

• High-power laser systems
• Ultrafast optics
• Fiber laser technology

Background:

• Fiber laser systems offer advantages in terms of robustness and cost-effectiveness for high-power applications.
• Scaling pulse energy in ultrafast fiber lasers is crucial for various scientific and industrial applications.

Purpose of the Study:

• To implement and demonstrate a novel pulse-energy scaling technique in a high-power ultrafast fiber laser system.
• To achieve the highest pulse energy from a fiber chirped-pulse amplification (CPA) system.

Main Methods:

• Utilized electro-optically controlled divided-pulse amplification for pulse-energy scaling.
• Employed coherent beam combination of multiple amplified pulse replicas.
• Integrated a fiber-based front end and a multipass-cell-based back end for modularity and a small footprint.
• Amplified bursts of eight pulses in parallel using ytterbium-doped large-pitch fiber amplifiers.

Main Results:

• Achieved a pulse energy of 23 mJ.
• Generated an average power of 674 W.
• Compressed the output pulse to a duration of 235 fs.
• Demonstrated the highest pulse energy for a fiber CPA system to date.

Conclusions:

• The demonstrated technique enables significant pulse-energy scaling in ultrafast fiber laser systems.
• Coherent beam combination is effective for achieving high-energy output from multiple parallel amplifiers.
• This advancement paves the way for new applications requiring high-energy ultrafast pulses from fiber lasers.