Fingerprints of slingshot non-sequential double ionization on two-electron probability distributions

G P Katsoulis,A Emmanouilidou

doi:10.1038/s41598-019-55066-1

G P Katsoulis, A Emmanouilidou

Open Access

https://doi.org/10.1038/s41598-019-55066-1

Copy DOI

Journal: Scientific Reports	Publication Date: Dec 1, 2019
Citations: 1	License type: open-access

Affiliation: University College London

Abstract

We study double ionization of He driven by near-single-cycle laser pulses at low intensities at 400 nm. Using a three-dimensional semiclassical model, we identify the pathways that prevail non-sequential double ionization (NSDI). We focus mostly on the delayed pathway, where one electron ionizes with a time-delay after recollision. We have recently shown that the mechanism that prevails the delayed pathway depends on intensity. For low intensities slingshot-NSDI is the dominant mechanism. Here, we identify the differences in two-electron probability distributions of the prevailing NSDI pathways. This allows us to identify properties of the two-electron escape and thus gain significant insight into slingshot-NSDI. Interestingly, we find that an observable fingerpint of slingshot-NSDI is the two electrons escaping with large and roughly equal energies.

Highlights

We study double ionization of He driven by near-single-cycle laser pulses at low intensities at 400 nm
Using a 3D semiclassical model we investigate how two-electron probability distributions change for different non-sequential double ionization (NSDI) pathways as well as for different intensities below-the-recollision-threshold
We find that in slingshot-NSDI the electron that ionizes first does so along the polarization direction of the laser field

Summary

Introduction

We study double ionization of He driven by near-single-cycle laser pulses at low intensities at 400 nm. When He is driven by near-single-cycle pulses of 400 nm wavelength, we have shown that a new mechanism overtakes RESI in the delayed pathway of NSDI29, at small intensities below the recollision threshold. Due to the electron that ionizes last undergoing slingshot motion, the two electrons escape opposite to each other along the direction of the laser field This anti-correlated two-electron escape has previously been attributed to multiple recollisions, a mechanism that was put forth in the context of RESI30–34. The main NSDI pathways, which are considered in the current

Methods

Results

Conclusion