Overview of X-ray Thomson scattering measurements of extreme states of matter

TL;DR

This paper reviews the development and application of X-ray Thomson scattering (XRTS) for diagnosing extreme states of matter, highlighting experimental techniques, analysis methods, and future prospects.

Contribution

It provides a comprehensive overview of XRTS experiments, analysis techniques, and discusses future developments in the field.

Findings

XRTS can infer density, temperature, and ionization state of matter.

The review covers experiments at laser and free electron laser facilities.

Analysis methods have both advantages and limitations discussed.

Abstract

Since its first successful applications in the early 2000s, x-ray Thomson scattering (XRTS) has emerged as one of the most successful tools for the diagnostics of extreme states of matter in the laboratory. By sampling the dynamic structure factor of the electrons, XRTS is capable of giving detailed insights into the atomic-scale physics of the matter probed. Moreover, thermodynamic parameters, like the mass density, temperature, and ionization state, are routinely inferred from XRTS measurements, providing a comprehensive characterization of the sample probed. In addition, the dynamic structure factor is of considerable interest in its own right as it contains information on other effects such as the plasmon shift, miscibility between species, electronic states and potential transitions between these states. In this work, we provide an extensive overview of previous XRTS experiments at both traditional laser and X-ray free electron laser facilities, including information about the probed material (elements, conditions), scattering geometry, analysis methods as well as corresponding references. In addition, we briefly discuss the advantages and shortcomings of widely used analysis methods for XRTS spectra and reflect on upcoming future developments in XRTS experiments and theory.