Nonlinear XUV-optical transient grating spectroscopy at the Si L2,3–edge
May 6, 2019Nonlinear XUV-optical transient grating spectroscopy at the Si L2,3-edge: Time-resolved transient grating spectroscopy facilitates detailed studies of electron dynamics and transport phenomena by means of a periodic excitation of matter with coherent ultrashort light pulses. We demonstrated the element specificity of XUV TG (X-TG) experiments by tuning the photon energy across the Si L2,3-edge of Si3N4. We observe a shortening of the signal decay when increasing the XUV photon energy above the absorption edge. The analysis of the wavelength dependent signal shows that the faster decay is driven by the increase in the charge carrier density. From the decay constants the interband Auger coefficient at elevated temperatures and high electron densities has been determined.
(a) Scheme of the MINI-TIMER setup for performing FWM experiments. The incident XUV pulse (blue) is split (mirror M0) and combined (mirrors M1 and M2) at the sample position to be mixed with a temporally delayed optical pulse (red). The transmitted XTG signal is detected using a CCD detector. (b) X-TG signals as observed on the CCD detector and the corresponding time trace for 100 eV XUV excitation. The time delays dt for which the CCD images are shown are marked red in the time trace.
Reference: R. Bohinc, G. Pamfilidis, J. Rehault, P. Radi, C. Milne, J. Szlachetko, F. Bencivenga, F. Capotondi, R. Cucini, L. Foglia, C. Masciovecchio, R. Mincigrucci, E. Pedersoli, A. Simoncig, N. Mahne, A. Cannizzo, H.M. Frey, Z. Ollmann, T. Feurer, A.A. Maznev, K. Nelson, and G. Knopp “Nonlinear XUV-optical transient grating spectroscopy at the Si L2,3-edge”, Applied Physics Letters (https://doi.org/10.1063/1.508541)