RIKEN Center for Emergent Matter Science Emergent Phenomena Measurement Research Team

Team Leader: Tetsuo Hanaguri (D.Eng.)

Japanese Page

Research Summary

We experimentally study electronic states behind emergent phenomena in electron systems, such as high-temperature superconductivity and topological quantum phenomena. For this purpose, we use scanning tunneling microscopes working under combined extreme conditions of very low temperature, high magnetic field and ultra-high vacuum. Modern scanning-tunneling-microscopy technology enables us to obtain a “map of the electronic state” with atomic-scale spatial resolution and energy resolution as high as micro electron volt. We will make and analyze the maps of various materials and try to establish the relationships between material properties and electronic states. We also aim to improve and functionalize the scanning tunneling microscope and pursue the development of novel measurement techniques to discover new emergent phenomena in condensed matter.

Main Research Fields

Mathematical & Physical Sciences

Related Research Fields

Interdisciplinary Science & Engineering

Keywords

Superconductivity
Topological quantum phenomena
Scanning probe microscopy

Selected Publications

1. Machida, T., and Hanaguri, T.:
"Searching for Majorana quasiparticles at vortex cores in iron-based superconductors"
Prog. Theor. Exp. Phys. 2024, 08C103 (2024).
2. Yasui, Y., Iwata, K., Okazaki, S., Miyasaka, S., Sugimoto, Y., Hanaguri, T., Takagi, H., and Sasagawa T.:
"Closing of the Mott gap near step edges in NiS2"
Phys. Rev. B 110, 045139 (2024).
3. Butler, C.J., Yoshida, M., Hanaguri, T., and Iwasa, Y.:
"Behavior under magnetic field of resonance at the edge of the upper Hubbard band in 1T-TaS2"
Phys. Rev. B 107, L161107 (2023).
4. Butler, C.J., Kohsaka, Y., Yamakawa, Y., Bahramy, M.S., Onari, S., Kontani, H., Hanaguri, T. and Shamoto, S.:
"Correlation-driven electronic nematicity in the Dirac semimetal BaNiS2"
Proc. Natl. Acad. Sci. USA 119, e2212730119 (2022).
5. Machida, T., Nagai, Y. and Hanaguri, T.:
"Zeeman effects on Yu-Shiba-Rusinov states"
Phys. Rev. Res. 4, 033182 (2022).
6. Machida, T., Yoshimura, Y., Nakamura, T., Kohsaka, Y., Hanaguri, T., Hsing, C.-R., Wei, C.-M., Hasegawa, Y., Hasegawa, S. and Takayama, A.:
"Superconductivity near the saddle point in the two-dimensional Rashba system Si(111)-√3 ×√3-(Tl,Pb)"
Phys. Rev. B 105, 064507 (2022).
7. Kasahara, S., Suzuki, H., Machida, T., Sato, Y., Ukai, Y., Murayama, H., Suetsugu, S., Kasahara, Y., Shibauchi, T., Hanaguri, T. and Matsuda, Y.:
"Quasiparticle Nodal Plane in the Fulde-Ferrell-Larkin-Ovchinnikov State of FeSe"
Phys. Rev. Lett. 127, 257001 (2021).
8. Butler, C. J., Yoshida, M., Hanaguri, T. and Iwasa, Y.:
"Doublonlike Excitations and Their Phononic Coupling in a Mott Charge-Density-Wave System"
Phys. Rev. X 11, 011059 (2021).
9. Yasui, Y., Butler, C. J., Khanh, N. D., Hayami, S., Nomoto, T., Hanaguri, T., Motome, Y., Arita, R., Arima, T., Tokura, Y. and Seki, S.:
"Imaging the coupling between itinerant electrons and localised moments in the centrosymmetric skyrmion magnet GdRu2Si2"
Nature Commun. 11, 5925 (2020).
10. Shibauchi, T., Hanaguri, T. and Matsuda, Y.:
"Exotic Superconducting States in FeSe-based Materials"
J. Phys. Soc. Jpn. 89, 102002 (2020).