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arXiv 1901.089702019-01eess.IVphysics.optics

Pulse-to-pulse wavefront sensing at free-electron lasers using ptychography

Simone Sala, Benedikt J. Daurer, Michal Odstrcil, Flavio Capotondi, Emanuele Pedersoli, Max F. Hantke, Michele Manfredda, N. Duane Loh, Pierre Thibault, Filipe R. N. C. Maia

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The pressing need for the detailed wavefront properties of ultra-bright and ultra-short pulses produced by free-electron lasers (FELs) has spurred the development of several complementary characterization approaches. Here we present a method based on ptychography that can retrieve full high-resolution complex-valued wave functions of individual pulses. Our technique is demonstrated within experimental conditions suited for diffraction experiments in their native imaging state. This lensless technique, applicable to many other short-pulse instruments, can achieve diffraction-limited resolution.

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