Electron Dynamics and Correlations During High-Order Harmonic Generation in Be

Eric Kutscher; Anton N Artemyev; Philipp V Demekhin

doi:10.3389/fchem.2022.809137

Electron Dynamics and Correlations During High-Order Harmonic Generation in Be

Front Chem. 2022 Jan 31:10:809137. doi: 10.3389/fchem.2022.809137. eCollection 2022.

Authors

Eric Kutscher¹, Anton N Artemyev¹, Philipp V Demekhin¹

Affiliation

¹ Institut für Physik und CINSaT, Universität Kassel, Kassel, Germany.

Abstract

We investigate theoretically the high-order harmonic generation in beryllium atom irradiated by a short 1850 nm linearly polarized laser pulse in the intermediate strong-field ionization regime with the Keldysh parameter of 0.85. To this end, the respective time-dependent Schrödinger equation is solved by the time-dependent restricted-active-space configuration-interaction (TD-RASCI) method. By systematically increasing the active space of included configurations, we demonstrate an individual effect of different physical processes evoked by the pulse, which, all together, significantly enrich and extend the computed high-order harmonic generation spectrum.

Keywords: electron correlations; high-harmonic generation; light-matter interaction; restricted-active-space; strong-field ionisation; theoretical and numerical methods.