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arXiv · 1607.01322

Imaging electron dynamics with time- and angle-resolved photoelectron spectroscopy

Daria Popova-Gorelova·Jochen Küpper·Robin Santra
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Abstract

We theoretically study how time- and angle-resolved photoemission spectroscopy can be applied for imaging coherent electron dynamics in molecules. We consider a process in which a pump pulse triggers coherent electronic dynamics in a molecule by creating a valence electron hole. An ultrashort extreme ultraviolet (XUV) probe pulse creates a second electron hole in the molecule. Information about the electron dynamics is accessed by analyzing angular distributions of photoemission probabilities at a fixed photoelectron energy. We demonstrate that a rigorous theoretical analysis, which takes into account the indistinguishability of transitions induced by the ultrashort, broadband probe pulse and electron hole correlation effects, is necessary for the interpretation of time- and angle-resolved photoelectron spectra. We show how a Fourier analysis of time- and angle-resolved photoelectron spectra from a molecule can be applied to follow its electron dynamics by considering photoelectron distributions from an indole molecular cation with coherent electron dynamics.

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Daria Popova-Gorelova, Jochen Küpper, Robin Santra. 2016-07-05. Imaging electron dynamics with time- and angle-resolved photoelectron spectroscopy. https://doi.org/10.1103/physreva.94.013412

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