First-principles simulations for attosecond photoelectron spectroscopy based on time-dependent density functional theory

TL;DR

This paper introduces a first-principles simulation method based on time-dependent density functional theory for attosecond photoelectron spectroscopy, accurately reproducing experimental results and enabling analysis of complex materials.

Contribution

A novel simulation framework that models the entire attosecond photoelectron spectroscopy process from excitation to detection using first-principles calculations.

Findings

Accurately reproduces RABBITT photoionization delays in Argon.

Shows good agreement with recent experimental measurements.

Provides a pathway to study microscopic processes in complex systems.

Abstract

We develop a first-principles simulation method for attosecond time-resolved photoelectron spectroscopy. This method enables us to directly simulate the whole experimental processes, including excitation, emission and detection on equal footing. To examine the performance of the method, we use it to compute the reconstruction of attosecond beating by interference of two-photon transitions (RABBITT) experiments of gas-phase Argon. The computed RABBITT photoionization delay is in very good agreement with recent experimental results from [Kl\"under et al, Phys. Rev. Lett. 106 143002 (2011)] and [Gu\'enot et al, Phys. Rev. A 85 053424 (2012)]. This indicates the significance of a fully-consistent theoretical treatment of the whole measurement process to properly describe experimental observables in attosecond photoelectron spectroscopy. The present framework opens the path to unravel the microscopic processes underlying RABBITT spectra in more complex materials and nanostructures.