Scalability of components for kW-level average power few-cycle lasers

Area of Science:

• Laser Physics and Photonics
• Nonlinear Optics
• Materials Science

Background:

• Femtosecond solid-state lasers are crucial for generating intense few-cycle laser pulses.
• Scaling these lasers to higher average power requires robust components capable of handling high energy throughput.
• Existing technologies face limitations in average power handling for critical optical elements.

Purpose of the Study:

• To investigate the average power scalability of essential components for intense few-cycle laser systems.
• To evaluate the performance of gas-filled waveguides, laser optics, and specialized mirrors under high-average-power conditions.
• To present a viable technological approach for scaling few-cycle lasers to kilowatt average power levels.

Main Methods:

• Testing of gas-filled waveguides (hollow capillary and Kagome-type photonic crystal fiber) under kilowatt continuous-wave (cw) laser operation.
• Evaluation of laser windows and mirrors (chirped and low dispersion) for high-average-power stability and thermal performance.
• Assessment of sapphire substrates' impact on the power handling of metal-coated mirrors.

Main Results:

• Demonstrated long-term stable transmission of kilowatt-level average power through both hollow capillary and Kagome-type photonic crystal fibers.
• Showed that sapphire substrates significantly enhance the average power capability of metal-coated mirrors.
• Confirmed negligible heating of ultrabroadband dielectric mirrors even at 1 kW of average power.

Conclusions:

• The investigated components are suitable for high-average-power operation in few-cycle laser systems.
• A clear technological pathway exists for scaling few-cycle lasers to and beyond 1 kW of average power.
• This research enables the development of next-generation high-power ultrashort pulse laser sources.