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arXiv · 2009.06480

Photoelectron spectroscopy of laser-dressed atomic helium

Severin Meister·Aaron Bondy·Kirsten Schnorr·Sven Augustin·Hannes Lindenblatt·Florian Trost·Xinhua Xie·Markus Braune·Rolf Treusch·Nicolas Douguet·Thomas Pfeifer·Klaus Bartschat·Robert Moshammer
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Abstract

Photoelectron emission from excited states of laser-dressed atomic helium is analyzed with respect to laser intensity-dependent excitation energy shifts and angular distributions. In the two-color XUV (exteme ultra\-violet) -- IR (infrared) measurement, the XUV photon energy is scanned between \SI{20.4}{\electronvolt} and the ionization threshold at \SI{24.6}{\electronvolt}, revealing electric dipole-forbidden transitions for a temporally overlapping IR pulse ($\sim\!\SI{e12}{\watt\per \centi\meter\squared}$). The interpretation of the experimental results is supported by numerically solving the time-dependent Schrödinger equation in a single-active-electron approximation.

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Severin Meister, Aaron Bondy, Kirsten Schnorr, Sven Augustin, Hannes Lindenblatt, Florian Trost, Xinhua Xie, Markus Braune, Rolf Treusch, Nicolas Douguet, Thomas Pfeifer, Klaus Bartschat, Robert Moshammer. 2020-09-14. Photoelectron spectroscopy of laser-dressed atomic helium. https://doi.org/10.1103/physreva.102.062809

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