Measuring the temporal coherence of a high harmonic generation setup employing a Fourier transform spectrometer for the VUV/XUV

• DOI: 10.1016/j.nima.2014.09.040
• Publication Date: 2014-09-21T21:37:53Z
• Authors: J.A. Terschlüsen; M. Agåker; M. Svanqvist; S. Plogmaker; J. Nordgren; J.-E. Rubensson; H. Siegbahn; J. Söderström
• Keywords: Spatial coherence; Fourier transform spectrometer; SoftX-ray; XUV; Atom and Molecular Physics and Optics; 0103 physical sciences; Atom- och molekylfysik och optik; HHG; Temporal coherence; 01 natural sciences

In this experiment we used an 800 nm laser to generate high-order harmonics in a gas cell filled with Argon. Of those photons, a harmonic with 42 eV was selected by using a time-preserving grating monochromator. Employing a modified Mach–Zehnder type Fourier transform spectrometer for the VUV/XUV it was possible to measure the temporal coherence of the selected photons to about 6 fs. We demonstrated that not only could this kind of measurement be performed with a Fourier transform spectrometer, but also with some spatial resolution without modifying the XUV source or the spectrometer.