Laser-induced electron Fresnel diffraction by XUV pulses at extreme intensity

TL;DR

This paper reveals a novel petal-like interference pattern in electron momentum distributions caused by Fresnel diffraction of electron wavepackets in super-intense XUV laser fields, supported by numerical and analytical models.

Contribution

It introduces the concept of laser-induced electron Fresnel diffraction in extreme UV fields and demonstrates its generality through numerical and analytical approaches.

Findings

Identification of petal-like interference structures in electron spectra.

Attribution of structures to Fresnel diffraction by the nucleus.

Validation via numerical solutions and analytical modeling.

Abstract

Ionization of atoms and molecules in laser fields can lead to various interesting interference structures in the photoelectron spectrum. For the case of a super-intense extreme ultraviolet laser pulse, we identify a novel petal-like interference structure in the electron momentum distribution along the direction of the laser field propagation. We show that this structure is quite general and can be attributed to the Fresnel diffraction of the electronic wavepacket by the nucleus. Our results are demonstrated by numerically solving the time-dependent Schrodinger equation of the atomic hydrogen beyond the dipole approximation. By building an analytical model, we find that the electron displacement determines the aforementioned interference pattern. In addition, we establish the physical picture of laser-induced electron Fresnel diffraction which is reinforced by both quantum and semiclassical models.