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arXiv · 1510.08698

Time-resolved four-wave-mixing spectroscopy for inner-valence transitions

Thomas Ding·Christian Ott·Andreas Kaldun·Alexander Blättermann·Kristina Meyer·Veit Stooß·Marc Rebholz·Paul Birk·Maximilian Hartmann·Andrew Brown·Hugo Van Der Hart·Thomas Pfeifer
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Abstract

Non-collinear four-wave mixing (FWM) techniques at near-infrared (NIR), visible, and ultraviolet frequencies have been widely used to map vibrational and electronic couplings, typically in complex molecules. However, correlations between spatially localized inner-valence transitions among different sites of a molecule in the extreme ultraviolet (XUV) spectral range have not been observed yet. As an experimental step towards this goal we perform time-resolved FWM spectroscopy with femtosecond NIR and attosecond XUV pulses. The first two pulses (XUV-NIR) coincide in time and act as coherent excitation fields, while the third pulse (NIR) acts as a probe. As a first application we show how coupling dynamics between odd- and even-parity inner-valence excited states of neon can be revealed using a two-dimensional spectral representation. Experimentally obtained results are found to be in good agreement with ab initio time-dependent R-matrix calculations providing the full description of multi-electron interactions, as well as few-level model simulations. Future applications of this method also include site-specific probing of electronic processes in molecules.

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Thomas Ding, Christian Ott, Andreas Kaldun, Alexander Blättermann, Kristina Meyer, Veit Stooß, Marc Rebholz, Paul Birk, Maximilian Hartmann, Andrew Brown, Hugo Van Der Hart, Thomas Pfeifer. 2015-10-29. Time-resolved four-wave-mixing spectroscopy for inner-valence transitions. https://doi.org/10.1364/ol.41.000709

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