Disappearance and reappearance of above-threshold-ionization peaks

TL;DR

This paper investigates the conditions under which above-threshold ionization peaks vanish and reappear, highlighting the role of nondipole effects and photoelectron momentum in intense laser fields.

Contribution

It introduces a method to predict and control the appearance of ionization peaks by accounting for photoelectron momentum shifts in nondipole regimes.

Findings

Ionization peaks disappear when nondipole effects are significant.

Reappearance of peaks is possible with knowledge of photoelectron momentum.

Findings are relevant for intense mid-infrared laser experiments.

Abstract

It is shown that above-threshold ionization peaks disappear when the kinetic energy associated with the nondipole radiation-pressure-induced photoelectron momentum in the laser propagation direction becomes comparable to the photon energy, and how peaks can be made reappear if knowledge of the length and direction of the photoelectron momentum is at hand and an emission-direction-dependent momentum shift is accounted for. The reported findings should be observable with intense mid-infrared laser pulses.