Picosecond pulse generated supercontinuum as a stable seed for OPCPA

Area of Science:

• Laser Physics
• Nonlinear Optics
• Materials Science

Background:

• Supercontinuum generation is crucial for various laser applications.
• Achieving stable and coherent supercontinuum generation, especially from bulk materials, remains challenging.
• Picosecond lasers offer a balance between high peak power and manageable nonlinear effects.

Purpose of the Study:

• To demonstrate stable supercontinuum generation in a bulk YAG crystal.
• To characterize the stability, coherence, and spectral properties of the generated supercontinuum.
• To assess the suitability of this picosecond-driven supercontinuum as a seed for Optical Parametric Amplifiers (OPCPA).

Main Methods:

• Utilizing a 3 ps, 1030 nm chirped pulse laser as the pump source.
• Employing a loose focus geometry within a 13 cm long YAG crystal for single-filament generation.
• Characterizing supercontinuum energy stability, spectral properties, coherence, and compressibility.

Main Results:

• Achieved highly stable supercontinuum (SC) generation with energy stability surpassing the pump laser by nearly a factor of 3.
• Demonstrated long-term spectral stability and high coherence of the generated SC.
• Confirmed the compressibility of SC spectral portions, indicating suitability for Fourier-limited pulse generation.

Conclusions:

• Stable, coherent, and compressible supercontinuum generation is feasible in bulk YAG crystals using picosecond chirped pulses.
• The demonstrated SC properties make it a promising and stable seed source for OPCPA systems.
• This method offers a robust approach for generating high-quality supercontinuum for advanced laser applications.