High-harmonic spectroscopy of transient two-center interference calculated with time-dependent density-functional theory

• Published in: Structural dynamics (Melville, N.Y.) Vol. 6; no. 4; pp. 044101 - 044101-10
• Main Authors: Mauger, François, Abanador, Paul M., Scarborough, Timothy D., Gorman, Timothy T., Agostini, Pierre, DiMauro, Louis F., Lopata, Kenneth, Schafer, Kenneth J., Gaarde, Mette B.
• Format: Journal Article
• Language: English
• Published: United States American Institute of Physics, Inc 01-07-2019; American Institute of Physics; American Crystallographic Association; AIP Publishing LLC and ACA
• Subjects: Attosecond pulses; Density functional theory; Electric fields; Group delay; Harmonic generations; Infrared lasers; Interference; Lasers; Orbits; Shape effects; Signal generation; Signal processing; Spectroscopy; Theory; Time dependence; Louisiana; Ohio; Baton Rouge Louisiana; United States > US
• ISSN: 2329-7778; 2329-7778
• DOI: 10.1063/1.5111349

We demonstrate high-harmonic spectroscopy in many-electron molecules using time-dependent density-functional theory. We show that a weak attosecond-pulse-train ionization seed that is properly synchronized with the strong driving mid-infrared laser field can produce experimentally relevant high-harmonic generation (HHG) signals, from which we extract both the spectral amplitude and the target-specific phase (group delay). We also show that further processing of the HHG signal can be used to achieve molecular-frame resolution, i.e., to resolve the contributions from rescattering on different sides of an oriented molecule. In this framework, we investigate transient two-center interference in CO2 and OCS, and how subcycle polarization effects shape the oriented/aligned angle-resolved spectra.