Sequential Single Shot X-ray Photon Correlation Spectroscopy at the SACLA Free Electron Laser

Area of Science:

• Condensed matter physics
• Materials science
• Photonics

Background:

• Hard X-ray free electron lasers (XFELs) offer unprecedented time and length scales for probing material dynamics.
• The stochastic nature of self-amplified spontaneous emission (SASE) in XFELs complicates established techniques like X-ray photon correlation spectroscopy (XPCS).

Purpose of the Study:

• To demonstrate a single-shot sequential XPCS approach suitable for XFEL environments.
• To overcome challenges posed by SASE fluctuations for XPCS measurements.
• To enable systematic XPCS studies at free electron laser sources.

Main Methods:

• Development and application of a single-shot sequential XPCS technique.
• Utilizing the SACLA free electron laser facility.
• Analysis of colloidal suspension dynamics with relaxation times matching the XFEL pulse repetition rate.

Main Results:

• Successful extraction of high-quality correlation functions from colloidal suspensions.
• Demonstration of XPCS feasibility at XFELs despite SASE noise.
• No observable sample damage during the experiments.

Conclusions:

• The developed single-shot sequential XPCS method is effective for studying dynamics at XFELs.
• This technique facilitates systematic investigations of materials at ultrafast timescales.
• Opens new avenues for condensed matter research using advanced XFEL capabilities.