Abstract
Angle-resolved photoemission spectroscopy (ARPES) is a powerful technique for directly probing the electronic structures of quantum materials, including high-temperature superconductors, topological materials, and low-dimensional systems [1]. Recent advances in synchrotron radiation sources and focused-beam optics have further extended the capability of ARPES from conventional band mapping to spatially resolved electronic structure measurements. At NanoTerasu, a new 3-GeV high-brilliance synchrotron radiation facility in Japan [2], we have developed BL06U, a soft-X-ray ARPES beamline dedicated to micro- and nano-focused ARPES experiments [3]. In this presentation, I will introduce the current status of BL06U, with particular focus on the high-resolution micro-ARPES system that has been available to general users since March 2025. I will then present recent applications of micro-ARPES to quantum materials, with emphasis on combinatorial electronic structure analysis. By utilizing high-dimensional ARPES datasets, this approach enables multiple physical parameters to be extracted from spatially resolved spectra and allows their correlations to be examined [4,5]. Such analysis opens a new pathway for studying spatial inhomogeneity and emergent electronic properties in quantum materials.
Biography
Hideaki Iwasawa is a principal researcher in the Institute for Advanced Synchrotron Light Source at National Institutes for Quantum Science and Technology (QST), Japan. He received his Ph.D. in Physics from the Tokyo University of Science for studying electronic structures of strongly correlated electron systems such as layered perovskite superconductors using angle-resolved photoemission spectroscopy (ARPES). Following his Ph.D. studies, he worked on developing and utilizing novel ARPES systems in synchrotron facilities, the Hiroshima Synchrotron Radiation Center at Hiroshima University, and Diamond Light Source. He currently works to develop an ARPES beamline with superior spatial resolutions at a new soft X-ray synchrotron radiation facility, NanoTerasu, in Tohoku, Japan. His recent research has centered on microscopic electronic structures of quantum materials by combining spatially-resolved ARPES and machine-learning-based analysis techniques.
References
[1] H. Iwasawa, Electron. Struct. 2, 043001 (2020).
[2] https://www.qst.go.jp/uploaded/attachment/18596.pdf
[3] K. Horiba et al., J. Phys.: Conf. Ser. 2380, 012034 (2022).
[4] H. Iwasawa et al., Phys. Rev. Res. 5, 043266 (2023).
[5] Y. Miyai et al., Sci. Technol. Adv. Mater. 25, 2379238 (2024).