Influence of Shape Resonances on the Angular Dependence of Molecular Photoionization Delays

TL;DR

This study investigates how shape resonances influence the angular dependence of molecular photoionization delays in NO molecules, combining experimental measurements with ab initio calculations to reveal attosecond-scale dynamics and their relation to scattering delays.

Contribution

It provides the first complete experimental and computational analysis of angular-dependent photoionization delays across a shape resonance in NO, using a multichannel Fano model and connecting delays to scattering theory.

Findings

Angular delays vary by hundreds of attoseconds due to resonant interference.

Resonance time delay is angle-independent in the Fano model.

Photoionization delays relate to Wigner scattering time delays.

Abstract

Characterizing time delays in molecular photoionization as a function of the ejected electron emission direction relative to the orientation of the molecule and the light polarization axis pro-vides unprecedented insights into the attosecond dynamics induced by extreme ultraviolet or X-ray one-photon absorption, including the role of electronic correlation and continuum resonant states. Here, we report completely resolved experimental and computational angular depend-ence of single-photon ionization delays in NO molecules across a shape resonance, relying on synchrotron radiation and time independent ab initio calculations. The angle-dependent time delay variations of few hundreds of attoseconds, resulting from the interference of the resonant and non-resonant contributions to the dynamics of the ejected electron, are well described using a multichannel Fano model where the resonance time delay is angle-independent. Comparing these results with the same resonance computed in e-NO+ scattering highlights the connection of photoionization delays with Wigner scattering time delays.