FLASH free-electron laser single-shot temporal diagnostic: terahertz-field-driven streaking

Area of Science:

• Physics
• Laser Science
• Spectroscopy

Background:

• Free-electron lasers (FELs) produce intense ultrashort X-ray pulses.
• Accurate characterization of these pulses is crucial for scientific applications.
• Existing methods for pulse duration and arrival time measurement have limitations.

Purpose of the Study:

• To report the commissioning of a novel terahertz-field-driven streak camera at the FLASH FEL.
• To achieve high-resolution measurements of XUV pulse duration and arrival time for single FEL pulses.
• To validate the stability and performance of the FLASH facility.

Main Methods:

• Installation and operation of a terahertz-field-driven streak camera at the FLASH FEL.
• Measurement of XUV photon pulse duration and arrival time with ~10 fs resolution.
• Comparison of terahertz-streaking measurements with spectral analysis methods and electron bunch arrival times.

Main Results:

• Pulse durations ranging from 300 fs down to <15 fs were measured for various FLASH FEL settings.
• A correlation width of 20 fs r.m.s. between XUV and electron bunch arrival times demonstrates FLASH stability.
• Terahertz-streaking measurements showed good agreement with results from spectral analysis.

Conclusions:

• The commissioned terahertz-streak camera is a powerful tool for characterizing ultrashort XUV FEL pulses.
• The results highlight the high stability and performance of the FLASH facility.
• This technique provides a reliable method for precise pulse duration and arrival time determination.