Femtosecond time-delay X-ray holography

• Published in: Nature Vol. 448; no. 7154; pp. 676 - 679
• Main Authors: Bogan, Michael J, Chapman, Henry N, London, Richard A, Woods, Bruce W, Bergh, Magnus, Caleman, Carl, Szöke, Abraham, Möller, Thomas, Treusch, Rolf, Bajt, Saša, Benner, W. Henry, Frank, Matthias, Plönjes, Elke, Huldt, Gösta, Marchesini, Stefano, Shapiro, David A, Hajdu, Janos, Boutet, Sébastien, Burmeister, Florian, Barty, Anton, Bostedt, Christoph, Kuhlmann, Marion, Seibert, M. Marvin, Spiller, Eberhard, Hau-Riege, Stefan P, Rohner, Urs
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 09.08.2007; Nature Publishing Group
• Subjects: Biological samples; Biophysics; Dynamics; Electrons; Exact sciences and technology; Explosions; Femtosecond; Fundamental areas of phenomenology (including applications); High resolution; Holography; Holography - methods; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Lasers; Measurement techniques; Microspheres; Monitors; NATURAL SCIENCES; NATURVETENSKAP; Optics; Physics; Polystyrenes - chemistry; TECHNOLOGY; TEKNIKVETENSKAP; Three dimensional; Time Factors; X- and γ-ray instruments and techniques; X-ray flashes; X-Rays; Time resolution; Free electron lasers; X-ray lasers; High field; Holography; Measuring methods; fs range; Explosions; Spherical particle; Pulsed lasers
• ISSN: 0028-0836; 1476-4687; 1476-4687; 1476-4679
• DOI: 10.1038/nature06049

Extremely intense and ultrafast X-ray pulses from free-electron lasers offer unique opportunities to study fundamental aspects of complex transient phenomena in materials. Ultrafast time-resolved methods usually require highly synchronized pulses to initiate a transition and then probe it after a precisely defined time delay. In the X-ray regime, these methods are challenging because they require complex optical systems and diagnostics. Here we propose and apply a simple holographic measurement scheme, inspired by Newton's 'dusty mirror' experiment, to monitor the X-ray-induced explosion of microscopic objects. The sample is placed near an X-ray mirror; after the pulse traverses the sample, triggering the reaction, it is reflected back onto the sample by the mirror to probe this reaction. The delay is encoded in the resulting diffraction pattern to an accuracy of one femtosecond, and the structural change is holographically recorded with high resolution. We apply the technique to monitor the dynamics of polystyrene spheres in intense free-electron-laser pulses, and observe an explosion occurring well after the initial pulse. Our results support the notion that X-ray flash imaging can be used to achieve high resolution, beyond radiation damage limits for biological samples. With upcoming ultrafast X-ray sources we will be able to explore the three-dimensional dynamics of materials at the timescale of atomic motion.