走査型透過電子顕微鏡(STEM)と電子エネルギー損失分光法(EELS)を組み合わせることで原子を直接見るだけではなく、その組成や電子状態を原子分解能で調べることができます。我々のグループでは原子分解能での電子状態解析や電子状態マップに関する研究を行っています。特に、近年ではモノクロメーターを装備した電子顕微鏡を導入したことで、高空間分解能だけではなく高エネルギー分解能での分光分析を行っています。

"Local electronic structure analysis for brownmillerite Ca(Sr)FeO2.5 using site-resolved energy-loss near-edge structures", M. Haruta, H. Kurata, K. Matsumoto, S. Inoue, Y. Shimakawa and S. Isoda; J. Appl. Phys., 110,033708 (8 pages) (2011).
"Visualization of hybridization state with atomic resolution using STEM-EELS", M. Haruta, K. Kurashima, T. Nagai, H. Komatsu, Y. Shimakawa, H. Kurata and K. Kimoto; Appl. Phys. Lett., 100, 163107 (2012).
"Detecting the direction of oxygen bonding in SrTiO3", M. J. Neish, N. R. Lugg, S. D. Findlay, M. Haruta, K. Kimoto and L. J. Allen; Phys. Rev. B., 88,115120 (2013).
"Atomic resolution chemical bond analysis of oxygen in La2CuO4", M. Haruta, T. Nagai, N. R. Lugg, M. J. Neish, M. Nagao, K. Kurashima, L. J. Allen, T. Mizoguchi, and K. Kimoto; J. Appl. Phys., 114,083712-1-8 (2013).
"Ca2FeMnO6: a layered double perovskite with unusually high valence Fe4+ in a layered arrangement", Yoshiteru Hosaka, Noriya Ichikawa, Takashi Saito, Mitsutaka Haruta, Koji Kimoto, Hiroki Kurata, and Yuichi Shimakawa; Bull. Chem. Soc. Jpn., 88,657-661 (2015).
"Determination of Elemental Ratio in an Atomic Column by Electron Energy-Loss Spectroscopy", Mitsutaka　Haruta,　Yoshiteru Hosaka, Noriya Ichikawa,Takashi Saito, Yuichi Shimakawa, Hiroki Kurata; ACS Nano, 10, 6680-6684 (2016).
"Melting of Oxygen Vacancy Order at Oxide−Heterostructure Interface", Kei Hirai, Ryotaro Aso, Yusuke Ozaki, Daisuke Kan, Mitsutaka Haruta, Noriya Ichikawa, Hiroki Kurata and Yuichi Shimakawa; ACS Appl. Mater. Interfaces , 9,30143−30148 (2017).
"Local quantification of coordination number for perovskite-related oxides using atomic resolution EELS maps", M. Haruta, H. Higuchi, T. Nemoto and H. Kurata, Appl. Phys. Lett., 113, 083110 (2018).
"Probing directionality of local electronic structure by momentum-selected STEM-EELS", A. Yamaguchi, M. Haruta, T. Nemoto and H. Kurata, Appl. Phys. Lett., 113,053101 (2018).(Featured, Scilight)
"Atomic-resolution two-dimensional mapping of holes in the cuprate superconductor La2−xSrxCuO4±δ", Mitsutaka Haruta, Yoshifumi Fujiyoshi, Takashi Nemoto, Akimitsu Ishizuka, Kazuo Ishizuka, and Hiroki Kurata, Physical Review B, 97,205139 (2018).
"Study of C K‑Edge High Energy Resolution Energy-Loss Near-Edge Structures of Copper Phthalocyanine and Its Chlorinated Molecular Crystals by First-Principles Band Structure Calculations",
Atsushi Yamaguchi, Takashi Nemoto, and Hiroki Kurata,
J. Phys. Chem. A (2020): https://dx.doi.org/10.1021/acs.jpca.9b10832