# Probing Electronic Fluxes via Time-Resolved X-ray Scattering

## TL;DR

This paper demonstrates that time-resolved X-ray scattering signals can reveal not only electron charge distributions but also electronic current flux densities, providing insights into ultrafast charge migration and electronic coherences.

## Contribution

It shows how X-ray scattering encodes electronic flux information, advancing the understanding of electron dynamics in out-of-equilibrium systems.

## Key findings

- X-ray scattering maps electronic current flux density
- Reveals electronic momentum distribution
- Provides timescales of electronic coherences

## Abstract

The current flux density is a vector field that can be used to describe theoretically how electrons flow in a system out-of-equilibrium. In this work, we unequivocally demonstrate that the signal obtained from time-resolved X-ray scattering does not only map the time-evolution of the electronic charge distribution, but also encodes information about the associated electronic current flux density. We show how the electronic current flux density qualitatively maps the distribution of electronic momenta and reveals the underlying mechanism of ultrafast charge migration processes, while also providing quantitative information about the timescales of electronic coherences.