On-line diagnostic tool for measurement of the time delay between two ultrashort light pulses

Research output: Contribution to journalArticle


Ultrafast accelerator-based sources combined with synchronized femtosecond lasers are currently being developed. The method described here is intended as a jitter monitor at such facilities. We report on the possibility of extracting a time-offset signal between two different synchronized ultrashort light pulses. The method is based on sum-frequency generation in a nonlinear crystal. Aiming at extracting the time-difference from visible pulsed radiation from an x-ray undulator and femtosecond laser pulses we are investigating the possibility of obtaining timing information when one of the two pulses is very weak (10(6) photons/pulse). This will enable on-line monitoring of the relative timing of an accelerator-based free-electron laser and a synchronized visible laser. The spatial position of the sum-frequency mixed region is registered using a position sensitive detector (PSD). We show that for an 80 fs light source the described electronic equipment is capable of delivering a signal proportional to the temporal shift of different ultrashort light pulses with an accuracy of approximately 30 fs in a time interval of several ps.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics
  • Subatomic Physics


  • position sensitive detector, femtosecond laser, detector calibration, auto/cross correlator, synchronization, time-resolved pump-probe, experiments
Original languageEnglish
Pages (from-to)1762-1767
JournalMeasurement Science & Technology
Issue number9
Publication statusPublished - 2004
Publication categoryResearch