Polaronic Effect in High-Harmonic Generation

TL;DR

This paper explores how electron-phonon interactions in the SSH chain influence high-harmonic generation, revealing spectrum modifications and increased harmonic yield through detailed quantum simulations.

Contribution

It introduces a model combining SSH chain dynamics with Holstein electron-phonon coupling to analyze HHG effects, highlighting the role of phonons in spectral modifications.

Findings

Phonons introduce new states within energy gaps.

Electron-phonon coupling enhances harmonic yield.

Spectrum modifications depend on phonon interactions.

Abstract

We investigate High-Harmonic Generation (HHG) in the Su-Schrieffer-Heeger (SSH) chain with electron-phonon coupling modeled via the Holstein interaction. The system dynamics are simulated using the tight-binding approximation, with local phonons approximated as quantum harmonic oscillators. Phononic degrees of freedom significantly expand the Hilbert space dimension. This interaction modifies the eigenenergy spectrum by introducing new states within previously existing gaps, enhancing the harmonic yield through additional allowed transitions.