Continuously tunable high photon flux high harmonic source

Area of Science:

• Physics
• Laser Science
• Quantum Optics

Background:

• Generation of tunable extreme ultraviolet (XUV) radiation is crucial for various scientific investigations.
• Existing methods often lack continuous tunability or require complex experimental setups.

Purpose of the Study:

• To present a continuously tunable XUV source with high photon flux.
• To demonstrate a simple yet effective method for spectral control in XUV generation.

Main Methods:

• Utilizing a high-power fiber laser coupled with a multipass cell.
• Employing waveguide-based high harmonic generation (HHG).
• Achieving spectral tuning via adjustments in laser pulse energy and exploiting nonlinear propagation effects and pulse chirping.

Main Results:

• Demonstration of a continuously tunable XUV source with photon flux >10^11 ph/s/eV.
• Spectral coverage achieved from 50 eV to 70 eV.
• High tuning speed, reproducibility, and reliability due to simple experimental design.

Conclusions:

• The presented waveguide-based HHG method provides a state-of-the-art tunable XUV source.
• The simple experimental realization ensures reproducible and reliable results.
• Future work may enable on-demand pulse-to-pulse switching of XUV radiation.