Ultrafast time-resolved Dark Field X-ray Microscopy for Light-Induced Structural Evolution

The type of atoms, their bonding, and arrangement in a crystal form the fundamental basis for determining a material's properties. However, most materials are not single crystals but rather polycrystalline, which implies the presence of lattice defects. These defects create regions with atomic arrangements different from the ideal lattice, directly influencing the material's properties. One example of this is that when the movement of dislocations is obstructed, the strengthening of the material increases. Consequently, understanding lattice defects has long been considered critical for both comprehending and designing the properties of materials, from past studies to recent research. DFXM (Dark-field X-ray Microscopy) has recently gained attention as a promising research non-destructive method for clearly visualizing domains and defects within materials. Additionally, DFXM at XFEL facilities is notable for enabling time-resolved dynamics studies with femtosecond laser pumping source.

In this presentation, I will begin discussion for the importance of understanding lattice defects. Following that, the concept of Dark-field X-ray microscopy for defect observation and provide an overview of the current state of research in this area will be presented. Lastly, I will report the recently completed installation of the time-resolved DFXM at PAL-XFEL, established through collaborative efforts, and present the recent findings obtained using this advanced technique.