Goldshteyn, J.; Bojahr, A.; Gaal, P.; Schick, D.; Bargheer, M.: Selective preparation and detection of phonon polariton wavepackets by stimulated Raman scattering. Physica Status Solidi B 251 (2014), p. 821-828

A new concept for shortening hard X-ray pulses emitted from a third-generation synchrotron source down to few picoseconds is presented. The device, called the PicoSwitch, exploits the dynamics of coherent acoustic phonons in a photo-excited thin film. A characterization of the structure demonstrates switching times of [less-than or equal to] 5 ps and a peak reflectivity of ~10-3. The device is tested in a real synchrotron-based pump-probe experiment and reveals features of coherent phonon propagation in a second thin film sample, thus demonstrating the potential to significantly improve the temporal resolution at existing synchrotron facilities.