Time-dependent R-matrix theory applied to two-photon double ionization of He

Abstract

We introduce a time-dependent R-matrix theory generalised to describe double ionization processes. The method is used to investigate two-photon double ionization of He by intense XUV laser radiation. We combine a detailed B-spline-based wavefunction description in a extended inner region with a single-electron outer region containing channels representing both single ionization and double ionization. A comparison of wavefunction densities for different box sizes demonstrates that the flow between the two regions is described with excellent accuracy. The obtained two-photon double ionization cross sections are in excellent agreement with other cross sections available. Compared to calculations fully contained within a finite inner region, the present calculations can be propagated over the time it takes the slowest electron to reach the boundary.

6 pages, 4 figures

References in corpus (5)

• Nonsequential two-photon double ionization of helium
• Time delay between photoemission from the 2p and 2s subshells of Neon
• A numerical study of two-photon ionization of helium using the Pyprop framework
• A combined R-matrix eigenstate basis set and finite-differences propagation method for the time-dependent Schr\"{od}dinger equation: the one-electron case
• Interference between competing pathways in harmonic generation

Cited by in corpus (7)

• Time-dependent generalized-active-space configuration-interaction approach to photoionization dynamics of atoms and molecules
• Population trapping in bound states during IR-assisted ultra-fast photoionization of Ne${}^{+}$
• Electron dynamics in the carbon atom induced by spin-orbit interaction
• Electron correlation effects in enhanced-ionization of diatomic molecules in near-infrared fields
• Angular distributions in two-colour two-photon ionization of He
• Coherent driving \emph{versus} decoherent dissipation in double inner-shell ionizations of neon atoms by attosecond pulses
• Fano resonance in XUV generated by helium with few-cycle intense laser pulses and its classical analogy