Polarization effects in attosecond photoelectron spectroscopy

TL;DR

This paper investigates how polarization effects influence attosecond photoelectron streaking spectra, revealing that they can cause apparent temporal shifts and must be considered for accurate time measurements in ultrafast spectroscopy.

Contribution

It demonstrates the impact of polarization-induced terms on streaking spectra and proposes methods to isolate and analyze these effects in molecular and atomic systems.

Findings

Polarization effects can cause an apparent 50 as temporal shift in hydrogen.

Polarization modifies the streaking spectrum, deviating from the vector potential mapping.

Angle-resolved spectroscopy can isolate polarization effects.

Abstract

We study the influence of polarization effects in streaking by combined atto- and femtosecond pulses. The polarization-induced terms alter the streaking spectrum. The normal streaking spectrum, which maps to the vector potential of the femtosecond pulse, is modified by a contribution following the field instead. We show that polarization effects may lead to an apparent temporal shift, that needs to be properly accounted for in the analysis. The effect may be isolated and studied by angle-resolved photoelectron spectroscopy from oriented polar molecules. We also show that polarization effects will lead to an apparent temporal shift of 50 as between photoelectrons from a 2p and 1s state in atomic hydrogen.