Extraction of attosecond time delay using the soft photon approximation

TL;DR

This paper introduces a method using the soft photon approximation to directly extract Wigner time delays from atomic photoionization experiments, simplifying the process by avoiding Coulomb-laser coupling corrections.

Contribution

The novel approach allows direct extraction of Wigner time delay from measurements without the need for Coulomb-laser correction, unlike previous methods.

Findings

Enables direct measurement of Wigner time delay

Eliminates the need for Coulomb-laser coupling corrections

Simplifies analysis of attosecond photoionization experiments

Abstract

We use the soft photon approximation to extract the Wigner time delay from atomic two-color photoionization experiments. Unlike the strong field approximation, the present method does not require introduction of the Coulomb-laser coupling corrections and enables one to extract the Wigner time delay directly from attosecond time delay measurements.