Electronic structure of superconductive diamond and related materials : Band insulator-metal transition and superconductivity

2010 Fiscal Year Final Research Report

• Project/Area Number: 20340091
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Okayama University
• Principal Investigator: YOKOYA Takayoshi Okayama University, 大学院・自然科学研究科, 教授 (90311646)
• Co-Investigator(Renkei-kenkyūsha): MURAOKA Yuji 岡山大学, 大学院・自然科学研究科, 准教授 (10323635) ; WAKITA Takanori 岡山大学, 大学院・自然科学研究科, 特任助教 (10423279)
• Project Period (FY): 2008 – 2010
• Keywords: 高濃度ホウ素ドープダイヤモンド超伝導体 / 半導体-金属転移 / 電子状態 / 光電子分光

Research Abstract

We have investigated evolution of electronic structure across semiconductor to metal transition of boron(B)-doped diamond and its related compounds by using photoemission spectroscopy. Soft x-ray angle-resolved photoemission spectroscopy has revealed valence band electronic dispersions of heavily B-doped superconductive diamond. Core level photoemission spectroscopy has showed multiple chemical sites of dopant atoms for heavily B- and phosphorous-doped diamond. For new superconductors, CaC_6 and potassium doped picene, evolution of electronic structure near the Fermi level due to intercalation and doping, respectively, have been observed directly, which provide insight into the mechanism of the superconductivity.

Research Products

• [Journal Article] Photoemission Study of Electronic Structure Evolution across the Metal-Insulator Transition of Heavily B-doped Diamond (2011)
  • Author(s): H.Okazaki, T.Arakane, K.Sugawara, T.Sato, T.Takahashi, T.Wakita, M.Hirai, Y.Muraoka, Y.Takano, S.Ishii, S.Iriyama, H.Kawarada, T.Yokoya
  • Journal Title: J.Phys.Chem.Solids 72 Pages: 582-584
  • Peer Reviewed
• [Journal Article] Multiple phosphorus chemical sites in heavily phosphorus-doped diamond (2011)
  • Author(s): H.Okazaki, R.Yoshida, T.Muro, T.Nakamura, T.Wakita, Y.Muraoka, M.Hirai, H.Kato, S.Yamasaki, Y.Takano, S.Ishii, T.Oguchi, T.Yokoya
  • Journal Title: Appl.Phys.Lett. 98 Pages: 082107
  • Peer Reviewed
• [Journal Article] Electronic structure of pristine and K-doped picene: Nonrigid band change and its implication for electron-intramolecular-vivration interaction (2010)
  • Author(s): H.Okazaki, T.Wakita, T.Muro, Y.Kaji, X.Lee, H.Mitamura, N.Kawasaki, Y.Kubozono, Y.Yamanari, T.kambe, T.Kato, M.Hirai, Y.Muraoka, T.Yokoya
  • Journal Title: Phys.Rev.B 82 Pages: 195114
  • Peer Reviewed
• [Journal Article] Spectroscopic evidence of the existence of substantial Ca 3d derived states at the Fermi level in the Ca-intercalated graphite superconductor CaC_6 (2009)
  • Author(s): H.Okazaki, R.Yoshida, K.Iwai, K.Noami, T.Muro, T.Nakamura, T.Wakita, Y.Muraoka, M.Hirai, F.Tomioka, Y.Takano, A.Takenaka, M.Toyoda, T.Oguchi, T.Yokoya
  • Journal Title: Phys.Rev.B 80 Pages: "035420-1"-"035420-5"
  • Peer Reviewed
• [Journal Article] Soft X-Ray Core-Level Photoemission Study of Boron Sites in Heavily Boron-Doped Diamond Films (2009)
  • Author(s): H.Okazaki, R.Yoshida, T.Muro, T.Wakita, M.Hirai, Y.Muraoka, Y.Takano, S.Iriyama, H.Kawarada, T.Oguchi, T.Yokoya
  • Journal Title: J.Phys.Soc.Jpn. 78 Pages: 034703
  • Peer Reviewed
• [Journal Article] Near E_F electronic structure of heavily boron-doped superconducting diamond (2008)
  • Author(s): H.Okazaki, T.Yokoya, J.Nakamura, N.Yamada, T.Nakamura, T.Muro, Y.Tamenori, T.Matsudhita, Y.Takata, T.Tokushima, S.Shin, Y.Takano, N.Nagao, T.Takenouchi, H.Kawarada, T.Oguchi
  • Journal Title: J.Phys.Chem.Soilds 69 Pages: 2978-2981
  • Peer Reviewed
• [Presentation] Photoemission Study of The Electronic Structure Evolution across Metal-Insulator Transition of Heavily B-doped Diamond (2010)
  • Author(s): Hiroyuki Okazaki, Takayuki Arakane, Katsuaki Sugawara, Takahumi Sato, Takashi Takahashi, Takanori Wakita, Masaaki Hirai, Yuji Muraoka, Yoshihiko Takano, Satoshi Ishii, Shingo Iriyama, Hiroshi Kawarada, Takayoshi Yokoya
  • Organizer: the 9th International Conference on Spectroscopies in Novel Superconductors (SNS2010) (5/23-5/28/2010)
  • Place of Presentation: Shanghai, Chaina
  • Year and Date: 2010-05-24
• [Presentation] 光電子分光による芳香族多環縮合炭化水素ピセンの電子状態 (2009)
  • Author(s): 岡崎宏之、室隆桂之、為則雄祐、脇田高徳、村岡祐治、平井正明、川崎菜穂子、加地由美子、久保園芳博、山成悠介、神戸高志、横谷尚睦
  • Organizer: 日本物理学会2009年秋季大会
  • Place of Presentation: 熊本大学黒髪キャンパス
  • Year and Date: 20090928-20090930
• [Presentation] Photoemission Spectroscopy of Doped Band Insulators and Related Superconductors (2009)
  • Author(s): Takayoshi Yokoya, Hiroyuki Okazaki, Takanori Wakita, Rikiya Yoshida, Masaaki Hirai, Yuji Muraoka
  • Organizer: The 9th International Conference on Materials and Mechanisms of Superconductivity (M^2S-IX)
  • Place of Presentation: Keio Plaza Hotel, Tokyo, Japan
  • Year and Date: 20090907-20090912
• [Presentation] Photoemission Study of Ca-intercalated Graphite Superconductor CaC_6 (2009)
  • Author(s): H.Okazaki, R.Yoshida, K.Iwai, K.Noami, T.Muro, T.Nakamura, T.Wakita, Y.Muraoka, M.Hirai, F.Tomioka, Y.Takano, A.Takenaka, M.Toyoda, T.Oguchi, T.Yokoya
  • Organizer: The 9th International Conference on Materials and Mechanisms of Superconductivity (M^2S-IX)
  • Place of Presentation: Keio Plaza Hotel, Tokyo, Japan
  • Year and Date: 20090907-20090912
• [Presentation] Photoemission spectroscopy study of heavily boron doped diamond and silicon electronic structures (2008)
  • Author(s): T.Wakita, H.Okazaki, K.Saeki, M.Ono, T.Eguchi, T.Okuda, A.Harasawa, I.Matsuda, Y.Hasegawa, Y.Takano, M.Hirai, Y.Muraoka, T.Yokoya
  • Organizer: The 2nd International Symposium on Anomalous Quantum Materials (ISAQM2008) and the 7th Asia-Pacific Workshop
  • Place of Presentation: 東京大学本郷キャンパス
  • Year and Date: 2008-11-09