Research Area

• Design of novel functionalities in oxide nanostructures

Research Subjects

• Control and design of novel functionalities of oxide nanostructures
• Exploration of multi-functionalities based on oxide nanostructures and application to novel devices
• Characterization of electronic, magnetic, and orbital structures at surface and heterointerface using synchrotron-radiation analysis
• Development and application of photoemission spectroscopy and x-ray absorption spectroscopy

Overview of Research

Our goal is to control and design the novel functionalities appearing in the nanostructure of transition metal oxides by the best possible combination of the sophisticated oxide growth techniques using molecular beam epitaxy and advanced analysis techniques using synchrotron radiation. The wide range of properties exhibited by the oxide nanostructures makes them one of the most interesting groups of functional materials. The novel physical properties arise from the interface region between two different materials. Thus, in order to control the novel functionalities, it is desired to obtain the knowledge of the interfacial electronic, magnetic, and orbital structures. For this purpose, in our laboratory, we utilize state-of-the-art spectroscopic techniques, such as angle-resolved photoemission spectroscopy and dichroic X-ray absorption spectroscopy using synchrotron radiation, which enable us to probe these structures in the nm-scale region.

Selected Publications

• Resonant tunneling driven metal-insulator transition in double quantum-well structures of strongly correlated oxide
  R. Yukawa, M. Kobayashi, T. Kanda, D. Shiga, K. Yoshimatsu, S. Ishibashi, M. Minohara, M. Kitamura, K. Horiba, A. F. Santander-Syro, and H. Kumigashira Nat. Commun. 12, 7070[1-7] (2021).
• Direct synthesis of metastable λ-phase Ti3O5 films on LaAlO3 (110) substrates at high temperatures
  Kohei Yoshimatsu and Hiroshi Kumigashira Cryst. Growth Des., 22, 703-710 (2022).
• Thickness dependence of electronic structures in VO2 ultrathin films: Suppression of the cooperative Mott-Peierls transition
  D. Shiga, B. E. Yang, N. Hasegawa, T. Kanda, R. Tokunaga, K. Yoshimatsu, R. Yukawa, M. Kitamura, K. Horiba, and H. Kumigashira Phys. Rev. B 102, 115114[1-8] (2020).
• Origin of the Anomalous Mass Renormalization in Metallic Quantum Well States of Strongly Correlated Oxide SrVO3
  M. Kobayashi, K. Yoshimatsu, E. Sakai, M. Kitamura, K. Horiba, A. Fujimori, and H. Kumigashira Phys. Rev. Lett. 115, 076801 (2015).
• Metallic Quantum Well States in Artificial Structures of Strongly Correlated Oxide
  K. Yoshimatsu, K. Horiba, H. Kumigashira, T. Yoshida, A. Fujimori, and M. Oshima Science 333, 319-322 (2011).

Contact Information

“Please delete “/” after “@” in a mail address.”
Hiroshi KUMIGASHIRA
（TEL +81-22-217-5802, E-mail: kumigashira@/tohoku.ac.jp）
Daisuke SHIGA
（TEL +81-22-217-5801, E-mail: dshiga@/tohoku.ac.jp）