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Updated: Sep 19, 2025
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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
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A cross-correlator-based timing tool for FemtoMAX
1MAX IV Laboratory, Lund University, PO Box 118, SE-221 00 Lund, Sweden.
Journal of Synchrotron Radiation
|June 2, 2025
Summary
We developed an ultrafast timing diagnostic using sum-frequency generation to precisely measure the time delay between synchronized X-ray pulses and laser pulses, achieving sub-30 fs accuracy.
Area of Science:
- Physics
- Optics
- Materials Science
Background:
- Synchronizing ultrashort light pulses is crucial for pump/probe experiments.
- Existing methods for timing diagnostics have limitations in accuracy and scope.
Purpose of the Study:
- To commission a novel ultrafast timing diagnostic system.
- To enable online monitoring of the relative timing between hard X-ray pulses and synchronized visible laser pulses.
Main Methods:
- Utilized sum-frequency generation in a nonlinear crystal.
- Employed a setup analogous to auto/cross-correlators.
- Combined a weak visible diagnostic beam from FemtoMAX with an intense synchronized laser beam.
Main Results:
- Achieved sub-30 femtosecond (fs) timing accuracy for pulses <50 fs (FWHM).
- Demonstrated the capability to measure time offsets within a 4 picosecond (ps) interval.
- Successfully enabled online monitoring of X-ray source and laser synchronization.
Conclusions:
- The developed diagnostic offers high accuracy for synchronizing X-ray and laser pulses.
- The method is suitable for online monitoring in pump/probe experiments.
- The system's advantages and limitations were discussed for future applications.
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