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arXiv · 1310.3355

CITIUS: an IR-XUV light source for fundamental and applied ultrafast science

C. Grazioli·C. Callegari·A. Ciavardini·M. Coreno·F. Frassetto·D. Gauthier·D. Golob·R. Ivanov·A. Kivimäki·B. Mahieu·Bojan Bucar·M. Merhar·P. Miotti·L. Poletto·E. Polo·B. Ressel·C. Spezzani·G. De Ninno
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Abstract

We present the main features of CITIUS, a new light source for ultrafast science, generating tunable, intense, femtosecond pulses in the spectral range from IR to XUV. The XUV pulses (about 10^5-10^8 photons/pulse in the range 14-80 eV) are produced by laser-induced high-order harmonic generation in gas. This radiation is monochromatized by a time-preserving monochromator, allowing also to work with high-resolution bandwidth selection. The tunable IR-UV pulses (10^{12}-10^{15} photons/pulse in the range 0.4-5.6 eV) are generated by an optical parametric amplifier, which is driven by a fraction of the same laser pulse that generates high order harmonics. The IR-UV and XUV pulses follow different optical paths and are eventually recombined on the sample for pump-probe experiments. The new light source will become the fulcrum of a new center located at the University of Nova Gorica, active in a wide range of scientific fields, including materials science, catalysis, biochemistry and magnetism. We also present the results of two pump-probe experiments: with the first one, we fully characterized the temporal duration of harmonic pulses in the time-preserving configuration; with the second one, we demonstrated the possibility of using CITIUS for studying of ultra-fast dynamics.

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C. Grazioli, C. Callegari, A. Ciavardini, M. Coreno, F. Frassetto, D. Gauthier, D. Golob, R. Ivanov, A. Kivimäki, B. Mahieu, Bojan Bucar, M. Merhar, P. Miotti, L. Poletto, E. Polo, B. Ressel, C. Spezzani, G. De Ninno. 2013-10-12. CITIUS: an IR-XUV light source for fundamental and applied ultrafast science. https://doi.org/10.1063/1.4864298

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