Characterizing Particle-Like Charge Migration Dynamics with High-Harmonic Sideband Spectroscopy

TL;DR

This paper introduces high-harmonic sideband spectroscopy (HHSS) as a new method to probe attosecond charge migration in molecules, revealing how CM dynamics influence HHG spectra.

Contribution

The study demonstrates that HHSS can effectively characterize charge migration dynamics in molecules, providing detailed temporal information through spectral analysis.

Findings

CM dynamics induce sidebands in HHG spectra.

Monitoring spectral changes reveals charge migration characteristics.

HHSS offers a robust probe for attosecond charge dynamics.

Abstract

We introduce high-harmonic sideband spectroscopy (HHSS) and show that it can be a robust probe of attosecond charge migration (CM) in a halogenated carbon-chain molecule. We simulate both the CM and 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.