Shot-to-shot intensity and wavefront stability of high-harmonic generation

Area of Science:

• Physics
• Quantum Optics
• Laser Science

Background:

• High-harmonic generation (HHG) is a crucial process for producing extreme ultraviolet (XUV) and soft X-ray radiation.
• Characterizing the shot-to-shot stability of HHG, particularly its spatial phase, is essential for advanced applications.
• Previous methods for spatial phase measurement in HHG were often time-integrated or lacked single-shot capabilities.

Purpose of the Study:

• To report on the shot-to-shot stability of intensity and spatial phase in high-harmonic generation (HHG).
• To introduce and validate a novel single-shot measurement of spatial phase using an XUV wavefront sensor with a Hartmann sensor.
• To compare single-shot spatial phase measurements with time-integrated measurements.

Main Methods:

• Intensity stability was quantified for each high-harmonic (HH) order using a spectrometer.
• Spatial phase was measured in a single shot for a single HH order utilizing an XUV wavefront sensor.
• Single-shot spatial phase measurements were compared against time-integrated measurements.

Main Results:

• The study demonstrates the capability to measure shot-to-shot intensity stability for individual high-harmonic orders.
• A novel single-shot measurement of spatial phase for HHG using a Hartmann wavefront sensor was successfully implemented.
• Comparison confirmed the XUV wavefront sensor's utility for simultaneous optimization of spatial phase and intensity within the studied HHG parameter space.

Conclusions:

• The developed XUV wavefront sensor provides a valuable tool for real-time characterization and optimization of HHG.
• Single-shot spatial phase measurement offers significant advantages over time-integrated methods for HHG stability analysis.
• This work enhances control over HHG, paving the way for more stable and predictable XUV/soft X-ray sources.