2D quantum-path interference in high-harmonic generation driven by highly-bichromatic fields
Abstract
We experimentally observe a new type of quantum-path interference, in two-dimensions (2D-QPI), in high-harmonic generation (HHG) driven by an orthogonally-polarised highly-bichromatic field. This regime is marked by comparable intensities of the two orthogonal colours. In this highly-bichromatic regime, we demonstrate that 2D-QPI is encoded in the measured harmonic intensity modulations with respect to the relative phase of the two-colour field. The modulations of the odd-order harmonics show a monomodal behaviour, whereas the even harmonics are modulated in a bimodal structure. Our calculations using the strong-field approximation and saddle-point method disentangle contributions from multiple quantum orbits in this HHG regime, revealing that the dipole response for both odd and even harmonics inherits the dynamic symmetry of the orthogonally-polarised driving field. This new type of 2D-QPI offers a novel route to HHG spectroscopy of attosecond electron dynamics by lifting up the dimensionality of the quantum paths involved in the interference.
Cite
@article{arxiv.2604.12838,
title = {2D quantum-path interference in high-harmonic generation driven by highly-bichromatic fields},
author = {Xiaozhou Zou and Lucie Jurkovičová and Anne Weber and Cong Zhao and Martin Albrecht and Ondřej Finke and Alexandr Vendl and Annika Grenfell and Wojciech Szuba and Jaroslav Nejdl and Eric Constant and Margarita Khokhlova and Emilio Pisanty and Ondřej Hort and Amelle Zaïr},
journal= {arXiv preprint arXiv:2604.12838},
year = {2026}
}