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DOE OSTI · 1979624

Characterizing particle-like charge-migration dynamics with high-order harmonic sideband spectroscopy

Hamer, Kyle A.·Mauger, François·Folorunso, Aderonke S.·Lopata, Kenneth·Jones, Robert R.·DiMauro, Louis F.·Schafer, Kenneth J.·Gaarde, Mette B.
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Abstract

Here, we introduce high-order harmonic sideband spectroscopy and show that it can be a robust probe of charge migration (CM) in a halogenated carbon-chain molecule. We simulate both the CM and high-order harmonic generation (HHG) dynamics using ab initio time-dependent density-functional theory. We find that CM dynamics initiated along the molecular backbone induces sidebands in the HHG spectrum driven by a delayed laser pulse that is polarized perpendicular to the molecular axis. Monitoring the spectrum as either the HHG laser frequency or the relative delay is scanned allows for the extraction of detailed information about the time-domain characteristics of the CM process.

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74 ATOMIC AND MOLECULAR PHYSICSChemical physics & physical chemistryHigh-order harmonic generationOpticsPhysicsTime-dependent DFTUltrafast phenomena

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Hamer, Kyle A., Mauger, François, Folorunso, Aderonke S., Lopata, Kenneth, Jones, Robert R., DiMauro, Louis F., Schafer, Kenneth J., Gaarde, Mette B.. 2022-07-07. Characterizing particle-like charge-migration dynamics with high-order harmonic sideband spectroscopy. https://doi.org/10.1103/physreva.106.013103

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