High-order harmonic generation from C$_{20}$ isomers

TL;DR

This study compares high-order harmonic generation in three C20 isomers—fullerene, ring, and bowl—using a modified Lewenstein model, revealing how molecular geometry influences harmonic spectra and polarization.

Contribution

It introduces a detailed analysis of harmonic responses from different C20 isomers, highlighting the role of molecular structure and interference effects in shaping the spectra.

Findings

Distinct modulation patterns in harmonic spectra for each isomer

Harmonic intensities are affected by multi-center interference

Molecular geometry influences harmonic polarization

Abstract

High-order harmonic responses from three $C_{20}$ isomers: fullerene, ring, and bowl, are calculated within the modified Lewenstein model for molecular systems. Spectra for all three structures exhibit intense modulations of the harmonic spectrum along the plateau and some of them can be interpreted as a consequence of multi-center interference effects. Each structure shows characteristic modulation patterns in peak harmonic intensities, which are directly related to zeroes in the recombination matrix element as a function of the three components of momentum. Different C$_{20}$ isomers lead to different harmonic polarizations depending on the geometric configuration of carbon atoms and molecular orientation.