Precise and accurate measurements of strong-field photoionisation and a transferrable laser intensity calibration standard

TL;DR

This paper presents highly accurate measurements of strong-field ionization yields for noble gases, establishing a transferable laser intensity calibration standard with 1.3% accuracy, crucial for attosecond science and model validation.

Contribution

It introduces a new laser intensity calibration standard based on hydrogen ionization, enabling precise measurements for noble gases in strong-field ionization experiments.

Findings

Achieved percent-level accuracy in ionization yield measurements for argon, krypton, and xenon.

Derived a transferrable laser intensity calibration standard with 1.3% accuracy.

Provided benchmark data for testing ionization models in noble gases.

Abstract

Ionization of atoms and molecules in strong laser fields is a fundamental process in many fields of research, especially in the emerging field of attosecond science. So far, demonstrably accurate data have only been acquired for atomic hydrogen (H), a species that is accessible to few investigators. Here we present measurements of the ionization yield for argon, krypton, and xenon with percentlevel accuracy, calibrated using H, in a laser regime widely used in attosecond science. We derive a transferrable calibration standard for laser peak intensity, accurate to 1.3%, that is based on a simple reference curve. In addition, our measurements provide a much-needed benchmark for testing models of ionisation in noble-gas atoms, such as the widely employed single-active electron approximation.