| SPring-8 | BL25SU、BL47XU、BL37XU、BL32B2 |
This research group focuses on advanced atomic structure analysis techniques such as X-ray fluorescence holography and photoelectron holography. These techniques enable direct visualization of the 3D atomic arrangement around a specific element and are particularly powerful for determining dopant sites in crystals. Because they are also sensitive to the displacement of surrounding atoms, they can be applied to the evaluation of lattice distortions in mixed crystal systems. To date, these methods have been successfully used to reveal dopant structures in functional materials such as semiconductors, superconductors, magnetic materials, and ferroelectrics, as well as atomic configurations of semiconductor interface defects and local structures in metalloproteins, providing new insights into the mechanisms underlying material properties. In addition, we have been developing measurement and analysis platforms to enable researchers to freely access these techniques. From the 1st to the 7th term of this research group, we have established fundamental measurement methodologies and further developed advanced experimental techniques, including valence-specific measurements, measurements under external fields, ultra-low-temperature measurements, and high-pressure measurements. As a result, the community of researchers utilizing these techniques has steadily expanded, and the research infrastructure for atomic-resolution holography has been significantly strengthened.
In the 8th term, looking toward the upgrade to SPring-8-II, we will examine new research directions such as the advancement of measurement techniques for micro-samples and micro-regions using focused X-rays, as well as the development of measurement methods for inhomogeneous and non-equilibrium materials. At the same time, the advanced techniques that have been promoted in this research group, including valence-specific measurements and measurements under high pressure, will continue to be further developed and applied to a wider range of material systems. Through these efforts, we aim to expand the research scope of atomic-resolution holography. Furthermore, we will explore collaborations with emerging data science approaches to enable efficient analysis of large datasets and to enhance methods for extracting structural information, thereby contributing to the development of new analytical frameworks. Through active discussions and interactions among participants, this research group will collect needs from diverse research fields and reflect them in the development of measurement and analysis techniques. Ultimately, the goal of this research group is to expand the user community and broaden the range of research fields utilizing atomic-resolution holography.