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arXiv · 1807.02183

Application of the Complex Kohn Variational Method to Attosecond Spectroscopy

Nicolas Douguet·Barry I. Schneider·Luca Argenti
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Abstract

The complex Kohn variational method is extended to compute light-driven electronic transitions between continuum wavefunctions in atomic and molecular systems. This development enables the study of multiphoton processes in the perturbative regime for arbitrary light polarization. As a proof of principle, we apply the method to compute the photoelectron spectrum arising from the pump-probe two-photon ionization of helium induced by a sequence of extreme ultraviolet and infrared-light pulses. We compare several two-photon ionization pump-probe spectra, resonant with the (2s2p)1P1o Feshbach resonance, with independent simulations based on the atomic B-spline close- coupling STOCK code, and find good agreement between the two approaches. This new finite-pulse perturbative approach is a step towards the ab initio study of weak-field attosecond processes in poly-electronic molecules.

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Nicolas Douguet, Barry I. Schneider, Luca Argenti. 2018-07-05. Application of the Complex Kohn Variational Method to Attosecond Spectroscopy. https://doi.org/10.1103/physreva.98.023403

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