Research Theme

Establishing Advanced Photoemission Methodologies for Novel Spin Materials Science

Keywords

Photoelectron Spectroscopy, Momentum Microscope, Electronic Spin Structure, Synchrotron Radiation

The electrons in the material are emitted into the vacuum as photoelectrons by being excited by photons. Interestingly, the angular distribution of such photoelectrons reveals a truly beautiful hologram pattern derived from the valence electron motion and the arrangement of atoms in the materials. Analyzing "art" based on the laws of physics sometimes leads to the discovery that connects the world of atoms with practical technology and application, which is the real pleasure of our research.

We constructed an advanced photoelectron momentum microscope (PMM) experimental station at the UVSOR Synchrotron Facility of IMS. The PMM is a novel concept analyzer for imaging photoelectron hologram and Fermi surface patterns from a μm-sized area. Furthermore, we are developing our own 3D spin vector imaging system and element-selective resonant-photoelectron-diffraction-spectroscopy technique.

Electron spins, which we pay particular attention to, are the source of various physical properties and functions such as magnetism, superconductivity, and topology. We aim to pioneer cutting-edge spin material science through comprehensive and detailed characterization of electrons.

Photoelectron momentum microscope at BL6U of UVSOR synchrotron facility together with valence photoelectron holograms and dispersions of TaS₂ and Bi₂Se₃. Charge density wave phase transition and topological nature can be directly studies in detail.

Selected Publications

1. F. Matsui, Y. Okano, H. Matsuda, T. Yano, E. Nakamura, S. Kera, S. Suga, "Domain-resolved Photoelectron Microscopy and μm-scale Momentum-resolved Photoelectron Spectroscopy of Graphite Armchair Edge Facet" J. Phys. Soc. Jpn., 91, 094703 (2022).
2. F. Matsui, S. Suga, "Coupling of kz-dispersing π bands with surface localized states in graphite" Phys. Rev. B, 105, 235126 (2022).
3. F. Matsui, S. Makita, H. Matsuda, E. Nakamura, Y. Okano, T. Yano, S. Kera, S. Suga, "Valence Band Dispersion Embedded in Resonant Auger Electrons" J. Phys. Soc. Jpn., 90, 124710 (2021).
4. F. Matsui, S. Makita, H. Matsuda, T. Yano, E. Nakamura, K. Tanaka, S. Suga, S. Kera, "Photoelectron Momentum Microscope at BL6U of UVSOR-III synchrotron" Jpn. J. Appl. Phys., 59, 067001 (2020).
5. F. Matsui, T. Matsushita, H. Daimon, "Holographic reconstruction of photoelectron diffraction and its circular dichroism for local structure probing" J. Phys. Soc. Jpn., 87, 061004 (2018).
6. F. Matsui, H. Nishikawa, H. Daimon, M. Muntwiler, M. Takizawa, H. Namba, T. Greber, "The 4π kz periodicity in photoemission from graphite" Phys. Rev. B, 97, 045430 (2018).
7. F. Matsui, M. Fujita, T. Ohta, N. Maejima, H. Matsui, H. Nishikawa, T. Matsushita, H. Daimon, "Selective Detection of Angular-Momentum-Polarized Auger Electrons by Atomic Stereography" Phys. Rev. Lett., 114, 015501 (2015).