Two-dimensional electron dynamics reconstructed by polarization-resolved high harmonic spectroscopy
Phys. Rev. A 113, 023114 – Published 19 February, 2026
DOI: https://doi.org/10.1103/zvwp-by3h
Abstract
We propose a polarization-resolved high harmonic spectroscopy scheme, which overcomes the limitations of the previous schemes when adopted in the two-dimensional (2D) synthetic driving fields. By numerically simulated experiments, we demonstrate the reconstruction of 2D electron trajectories driven by orthogonal two-color (OTC) fields with comparable intensities. Our method makes full use of the dynamical symmetry of the OTC field. Two weak lasers with different frequencies and polarizations are employed to perturb the balance of the subcycle interferometer, respectively. The electron dynamics are imprinted on the ellipticity modulation of high harmonics. The measured birth time of the attosecond pulse corresponds well with that calculated by the Gabor transform, and the average deviation is less than 10 as. Our results demonstrate that the electron has a nonzero longitudinal velocity at the ionization time, supporting the nonadiabatic tunneling regime. In addition, the nonzero tunneling exits are also reconstructed. Our work highlights the importance of the polarization information of harmonic spectra in reconstructions, especially for 2D problems.
