Harmonic generation of noble-gas atoms in the Near-IR regime using ab-initio time-dependent R-matrix theory

TL;DR

This paper uses advanced ab-initio time-dependent R-matrix theory to accurately simulate harmonic generation in noble-gas atoms at Near-IR wavelengths, revealing atomic structure effects and multielectron interactions.

Contribution

It demonstrates the first application of ab-initio time-dependent R-matrix theory to model harmonic generation spectra in noble gases at Near-IR wavelengths, capturing complex atomic effects.

Findings

Identification of a Cooper minimum in Kr harmonic spectra

Observation of a giant resonance in Xe spectra

Good agreement between theoretical and experimental spectra

Abstract

We demonstrate the capability of ab-initio time-dependent R-matrix theory to obtain accurate harmonic generation spectra of noble-gas atoms at Near-IR wavelengths between 1200 and 1800 nm and peak intensities up to 1.8 X 10(14) W/cm(2) . To accommodate the excursion length of the ejected electron, we use an angular-momentum expansion up to Lmax = 279. The harmonic spectra show evidence of atomic structure through the presence of a Cooper minimum in harmonic generation for Kr, and of multielectron interaction through the giant resonance for Xe. The theoretical spectra agree well with those obtained experimentally.