Focusing and collimation of laser-generated ultrashort x-ray pulses by polycapillary lenses

摘要

X-ray pulses from a fs-laser plasma were focused by an X-ray capillary lens, generating a spot smaller than 100 μm.Fe Kα radiation (λ = 0.194 nm) is produced by focusing 200 mJ/130 fs pulses from the ATLAS titanium-sapphirelaser at 10 Hz onto a moving iron tape. The capillary lens enhanced the intensity by a factor of about 1600.Diffraction from samples of small size is demonstrated by producing diffractograms from a Si (111) crystal in onlyabout 10 seconds. The model of a novel ultrafast streak camera which takes advantage of the different path lengths ofrays propagating through the lens is demonstrated. Preliminary experiments using a semi-lens for collimating X-raysare also reported.