Extreme Ultraviolet High-Harmonic Interferometry of Excitation-Induced Bandgap Dynamics in Solids
Abstract
Interferometry is a fundamental technique in physics, enabling precise measurements through the interference of waves. High-harmonic generation (HHG) in solids has emerged as a powerful method for probing ultrafast electronic dynamics within crystalline structures. In this study, we employed extreme ultraviolet (XUV) high-harmonic interferometry with phase-locked XUV pulse pairs to investigate excitation-induced bandgap dynamics in solids. Our experiments on amorphous SiO2 and crystalline MgO, complemented by analytical modeling and semiconductor Bloch equation simulations, reveal a correlation between transient bandgap modifications and variations in the phase of harmonic emission. These findings suggest a potential pathway for sub-cycle, all-optical control of band structure modifications, advancing prospects for petahertz-scale electronic applications and attosecond diagnostics of carrier dynamics.
Keywords
Cite
@article{arxiv.2502.20564,
title = {Extreme Ultraviolet High-Harmonic Interferometry of Excitation-Induced Bandgap Dynamics in Solids},
author = {Lisa-Marie Koll and Simon Vendelbo Bylling Jensen and Pieter J. van Essen and Brian de Keijzer and Emilia Olsson and Jon Cottom and Tobias Witting and Anton Husakou and Marc J. J. Vrakking and Lars Bojer Madsen and Peter M. Kraus and Peter Jürgens},
journal= {arXiv preprint arXiv:2502.20564},
year = {2025}
}