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The Petawatt‐Field‐Synthesizer (PFS) project at the Max‐Planck‐Institut fur Quantenoptik (Garching), aims at combining few‐cycle pulse durations with petawatt‐scale peak powers by using short pulses (on the few‐ps scale) for both seeding and pumping an optical parametric chirped pulse amplification (OPCPA) chain. Such a short‐pulse pumped OPCPA approach imposes very strict demands on the synchronization between the seed and the pump pulses, i.e. the timing jitter between the pulses has to be below the 100 fs‐level. We report on recent progress on the development of the PFS system, in particular about the investigation of the pump‐seed timing jitter. We have identified the grating stretcher/compressor setup of the pump laser chain as the main source of a temporal instability of about >200 fs rms and propose ways to eliminate this in order to allow for first short‐pusle pumped OPCPA experiments.

Latest developments in the field of laser-wakefield accelerators (LWFAs) have led to relatively stable electron beams in terms of peak energy, charge, pointing and divergence from mmsized accelerators. Simulations and LWFA theory indicate that these beams have low transverse emittances and ultrashort bunch durations on the order of ∼ 10 fs. These features make LWFAs perfectly suitable for driving high-brightness X-ray undulator sources and free-electron lasers (FELs) on a university-laboratory scale.With the detection of soft-X-ray radiation from an undulator source driven by laser-wakefield accelerated electrons, we succeeded in achieving a first milestone on this path. The source delivers remarkably stable photon beams which is mainly due to the stable electron beam and our miniature magnetic quadrupole lenses, which significantly reduce its divergence and angular shot-to-shot variation. An increase in electron energy allows for compact, tunable, hard-Xray undulator sources. Improvements of the electron beams in terms of charge and energy spread will put table-top FELs within reach. © 2010 American Institute of Physids.

Quasi-monoenergetic, laser-driven electron beams of up to ∼ 200 MeV in energy have been generated from steady-state-flow gas cells [1], These beams are emitted within a low-divergence cone of 2.1 ± 0.5 mrad FWHM and feature unparalleled shot-to-shot stability in energy (2.5% rms), pointing direction (1.4 mrad rms) and charge (16% rms) owing to a highly reproducible plasma-density profile within the laser-plasma-interaction volume. Laser-wakefield acceleration (LWFA) in gas cells of this type constitutes a simple and reliable source of relativistic electrons with well defined properties, which should allow for applications such as the production of extreme-ultraviolet undulator radiation in the near future. © 2009 American Institute of Physics.