Femtosecond Time Delay X-ray Holography

Conventional time-resolved optical methods require highly synchronized photon pulses to initiate a transition and then probe it at a precisely defined time delay. In the X-ray regime, these methods are challenging since they require complex optical systems and diagnostics. We have invented a holographic measurement scheme, inspired by Newton's “dusty mirror” experiment to monitor the X-ray-induced explosion of microscopic objects. The time delay is encoded in the diffraction pattern to an accuracy of better than one femtosecond, and the sample depth is holographically recorded to sub-wavelength accuracy. We applied this technique to follow the X-ray induced explosion of a sample irradiated by an intense pulse from FLASH, and observed that sample explosion occurs picoseconds after the femtosecond X-ray pulse traversed the sample. By varying the distance between the reflecting multilayer and the object, different time delays can be set (a new sample is needed for each shot). These results gave the first glimpses into early steps of plasma formation by X-rays.

References:

Chapman, H.; Hau-Riege, S.; Bogan, M.; Bajt, S.; Barty, A.; Boutet, S.; Marchesini, S.; Frank, M.; Woods, B. W.; Benner, W. H.; London, R. A.; Rohner, U.; Szoke, A.; Spiller, E.; Moller, T.; Bostedt, C.; Shapiro, D.; Kuhlmann, M.; Treusch, R.; Plonjes, E.; Burmeister, F.; Bergh, M.; Caleman, C.; Huldt, G.; Seibert, M. M.; Hajdu, J., "Femtosecond time-delay X-ray holography," Nature, 2007, 448, 676-679

 PULSE Research Nanoscale & Biomolecular Imaging • Publications • Scientific Staff