1998 Fiscal Year Annual Research Report

ナノグラファイトの端が担うメゾスコピックπ電子制御

Research Project

Project/Area Number	10309003
Research Category	Grant-in-Aid for Scientific Research (A)
Research Institution	Waseda University
Principal Investigator	大島忠平早稲田大学, 理工学部, 教授 (10212333)
Co-Investigator(Kenkyū-buntansha)	中田恭子青山学院大学, 理工学部, 専任講師 (20272742) 榎敏明東京工業大学, 大学院・理工学研究科, 教授 (10113424) 中尾憲治筑波大学, 物質工学系, 教授 (30011597)
Keywords	ナノグラファイト / グラファイトナノリボン / 端局在電子状態 / 端局在格子振動 / パイ電子 / 量子化バンド / スピングラス
Research Abstract	2種類のナノグラファイト結晶を作成し、以前に藤田等によって理論的に予想された端局在パイ電子バンドを検出した(大島・榎)。またこの端局在パイ電子状態の磁気特性、格子振動を理論的に調べ、端局在状態に特有な物性を見出し、さらに、この端局在状態のトポロジカル構造依存性や積層依存性を明らかにした(中尾・中田)。以下に、今年度の主な研究成果を列挙いたします。 (1) 幅0.8nmグラファイト・ナノリボンをCVD法で作成し、このリボンの量子化したパイ電子バンドとフェルミ準位近傍にフラットバンド(端局在電子状態)の存在を角度分解紫外線光電子スペクトルより確認した。 (2) ナノダイヤモンドの熱処理によって作成したナノグラファイトト及びナノグラファイト集合体の端局在状態の存在を、X-線、ラマン散乱、電顕、磁化率、ESRを使って確認した。また、ナノグラファイト集合体の端局在状態に帰属される電子スピンが低温でスピングラス状態を形成することを実験的に明らかにした。 (3) 端局在状態に起因した低温での強い常磁性を理論的に確認し、基底状態の端状態に起因するスピン揺らぎの効果を見出した。また、ナノグラファイトの格子振動の端局在振動モード出現の可能性を示した。 (4) 第一原理計算により、キノイド型の極限構造をもたないzigzagリボン(N=偶数)について最適化構造を得た。また、単層リボンで、構造や電子状態に対する強結合モデルでの描像が再現されることを確認した。さらに、グラファイトと同様なAB積層構造でも端局在状態が形成されることを明らかにした。

Research Products

(24 results)

All Other

All Publications (24 results)

[Publications] M Terai, N Hawasegawa, M Okuzawa S.Otani and C.Oshima: "Electronic states of monolayer micrographite on TiC(410)surface" Applied Surfcae Science. 130-132. 876-882 (1998)
[Publications] E.Rokuta, N.Yamamoto, Y.Hasegawa, M.Trenary, T.Nagao and S.Oshima: "Deformation of boron network at Lathanum boride(III)surface" Surface Science. 416. 363-370 (1998)
[Publications] E.Rokuta, Y.Hasegawa, A.Itoh, K.Yamashita, T.Tanaka, S.Otani and C.Oshima: "Vibrational Spectra of h-BN and Graphite films on Facetted Ni(755)" Surface Science (in press). Xx. Xx-xx (1999)
[Publications] K.Nagaoka, T.Yamashita, S.Uchiyama, M.Yamada, H.Fujii and C.Oshima: "Monopchromatic electron emission from the macrostopic quantum state" Nature. 396. 557-559 (1998)
[Publications] K.Nagaoka, T.Yamashita, S.Uchiyama, M.Yamada, H.Fujii and C.Oshima: "Angular resolved emission spectra from Nb." Applied Surface Science. 130-132. 512-517 (1998)
[Publications] C.Oshima, H.Fujii, T.Yamashita, S.Uchiyama, M.Yamada and K.Nagata: "Construction of a low-temperature gun and high-resolution emission spectra" Appled Surface Science(in press). 624. Xxx-xxx (1999)
[Publications] O.E.Andersson, B.L.V.Prasad, H.Sato, T.Enoki, Y.Hishiyama, Y.Kaburagi, M.Yoshikawa, and S.Bandow,: "The Structure and Electronic Properties of Graphite Nano-Particles,," Phys.Rev. B58(24), 16.16387 (1998)
[Publications] T.Yomashita, T.Enoki, T.Miyamae, and T.Miyazaki,: "The Contribution of Intercalate to the Electronic Structure and Transport Properties for Potassium-Oxygen-Graphite Intercalation Compounds" Mol.Cryst.Liq.Cryst,. 310. 243-248 (1998)
[Publications] O.E.Andersson, H.Sato, T.Enoki, M.Suzuki, and I.Suzuki: "The C-Axis Magnetoresistance and Themoelectric Power of CuC12 Graphite Intercalation Compounds" Mol.Cryst.Liq.Cryst.310. 249-254 (1998)
[Publications] Y.Shibayama, H.Sato, T.Enoki, M.Endo, and N.Shindo: "Magnetic Properties of Activated Carbon Fibers and Their Iodine-Doping Effect" Mol.Cryst.Liq.Cryst. 310. 273-278 (1998)
[Publications] N.Kobayashi, T.Enoki, C.Ishii, K.Kaneko, and M.Endo.: "Gas Adsorption Effects on Structural and Electrical Properties of Activated Carbon Fibers," J.Chem.Phys.109.5. 1983-1990 (1998)
[Publications] T.Enoki,: "Thermal and Mechanical Properties" “Functionality of Molecular Systems 1, From Molecules to Molecular Systemes", ed by S.Nagakura, Springer Verlag, Berlin, 1998. 225-240 (1998)
[Publications] 榎敏明: "新しく炭素材料実験を始める人のために-炭素材料の化学と電子スピン共鳴" 炭素. 181. 44-46 (1998)
[Publications] 榎敏明: "炭素同素体の電子物性と表面" ニューダイヤモンド. 50. 8-12 (1998)
[Publications] Toshiaki Enoki,: "Novel Carbon-Based Host-Guest Systems," Supercarbon, Synhesis, Properties and Applications, ed.By S.Yoshimura, Springer Series of Materials Science. 33. 137-146 (1998)
[Publications] K.Wakabayashi, M.Fujita K.usakabe and H.Ajiki: "Magnetic Field Effect on Graphite Ribbons" J.Mag.Mag Mat.177. 1485-1495 (1998)
[Publications] K.Wakabayashi M.Sigrist and M.Fujita: "Spin Wave Mode of Edge-Localized Magnetic States in Nanographite Zigzag Ribbons" J.Phys.Soc.Jpn.167. 2089-2094 (1998)
[Publications] K.Wakabayashi, M.Igami Y.Takagi, S.Okada, m.Fujita, K.Nakada and K.Kusakabe: "NOVEL ELECTRONIC PROPERTIES OF NANOGRAPHITE, HYPERGRAPHITE AND TOPOLOGICAL" Proceeding of 24th International Conference on Physics of Semiconductor, Jerusalem, Israel.Publishied from World Scientific Singapore. Aug. (1998)
[Publications] K.Wakabayashi, M.Fujita, H.Ajiki and M.Sigrist.: "Electronic and Magnetic Properties of Nanographite Ribbons" “Phys.Rev.B.April. (1999)
[Publications] M.Igami, M.Fujita, and S.Mizuno: "Edge Localized phonon in Nanogrephite Ribbons" Proceeding of Interntional Conference on Sience and Technology of Synthetic Metals, 1998 Montpellier, France.Synthetic Metals.July. (1999)
[Publications] M.Igami, T.Nakanishi and T.Ando: "Conductance of Carbon Nanotubes with a Vacancy" J.Phys.Soc.Jpn.March. (1999)
[Publications] Y.Takagi, M.Fujita, M.Igami, K.Wakabayashi and K.Nakada: "Electronic Structure and Surface Localized States of Hyper-Graphite Network" Proceeding of International Conference on Sience and Technology of Synthetic Metals, July.1998.Montpellier, France.Synthetic Metals. (1999)
[Publications] K.Nakada, M.Igami and M.Fujita,: "Electron-Electron Interaction in Nanographite Ribbons" J.Phys.Soc.Jpn.vol.67 no.7 1998 pp.2388-2394. 167. 2388-2394 (1998)
[Publications] Y.Miyamoto, K.Nakada and M.Fujita,: "First-principles study on edge state of H-terminated graphitic ribbons," Phys.Rev.B. 59. (1999)

1998 Fiscal Year Annual Research Report

ナノグラファイトの端が担うメゾスコピックπ電子制御

Principal Investigator

大島 忠平 早稲田大学, 理工学部, 教授 (10212333)

Research Products

[Publications] M Terai, N Hawasegawa, M Okuzawa S.Otani and C.Oshima: "Electronic states of monolayer micrographite on TiC(410)surface" Applied Surfcae Science. 130-132. 876-882 (1998)

[Publications] E.Rokuta, N.Yamamoto, Y.Hasegawa, M.Trenary, T.Nagao and S.Oshima: "Deformation of boron network at Lathanum boride(III)surface" Surface Science. 416. 363-370 (1998)

[Publications] E.Rokuta, Y.Hasegawa, A.Itoh, K.Yamashita, T.Tanaka, S.Otani and C.Oshima: "Vibrational Spectra of h-BN and Graphite films on Facetted Ni(755)" Surface Science (in press). Xx. Xx-xx (1999)

[Publications] K.Nagaoka, T.Yamashita, S.Uchiyama, M.Yamada, H.Fujii and C.Oshima: "Monopchromatic electron emission from the macrostopic quantum state" Nature. 396. 557-559 (1998)

[Publications] K.Nagaoka, T.Yamashita, S.Uchiyama, M.Yamada, H.Fujii and C.Oshima: "Angular resolved emission spectra from Nb." Applied Surface Science. 130-132. 512-517 (1998)

[Publications] C.Oshima, H.Fujii, T.Yamashita, S.Uchiyama, M.Yamada and K.Nagata: "Construction of a low-temperature gun and high-resolution emission spectra" Appled Surface Science(in press). 624. Xxx-xxx (1999)

[Publications] O.E.Andersson, B.L.V.Prasad, H.Sato, T.Enoki, Y.Hishiyama, Y.Kaburagi, M.Yoshikawa, and S.Bandow,: "The Structure and Electronic Properties of Graphite Nano-Particles,," Phys.Rev. B58(24), 16.16387 (1998)

[Publications] T.Yomashita, T.Enoki, T.Miyamae, and T.Miyazaki,: "The Contribution of Intercalate to the Electronic Structure and Transport Properties for Potassium-Oxygen-Graphite Intercalation Compounds" Mol.Cryst.Liq.Cryst,. 310. 243-248 (1998)

[Publications] O.E.Andersson, H.Sato, T.Enoki, M.Suzuki, and I.Suzuki: "The C-Axis Magnetoresistance and Themoelectric Power of CuC12 Graphite Intercalation Compounds" Mol.Cryst.Liq.Cryst.310. 249-254 (1998)

[Publications] Y.Shibayama, H.Sato, T.Enoki, M.Endo, and N.Shindo: "Magnetic Properties of Activated Carbon Fibers and Their Iodine-Doping Effect" Mol.Cryst.Liq.Cryst. 310. 273-278 (1998)

[Publications] N.Kobayashi, T.Enoki, C.Ishii, K.Kaneko, and M.Endo.: "Gas Adsorption Effects on Structural and Electrical Properties of Activated Carbon Fibers," J.Chem.Phys.109.5. 1983-1990 (1998)

[Publications] T.Enoki,: "Thermal and Mechanical Properties" “Functionality of Molecular Systems 1, From Molecules to Molecular Systemes", ed by S.Nagakura, Springer Verlag, Berlin, 1998. 225-240 (1998)

[Publications] 榎 敏明: "新しく炭素材料実験を始める人のために-炭素材料の化学と電子スピン共鳴" 炭素. 181. 44-46 (1998)

[Publications] 榎 敏明: "炭素同素体の電子物性と表面" ニューダイヤモンド. 50. 8-12 (1998)

[Publications] Toshiaki Enoki,: "Novel Carbon-Based Host-Guest Systems," Supercarbon, Synhesis, Properties and Applications, ed.By S.Yoshimura, Springer Series of Materials Science. 33. 137-146 (1998)

[Publications] K.Wakabayashi, M.Fujita K.usakabe and H.Ajiki: "Magnetic Field Effect on Graphite Ribbons" J.Mag.Mag Mat.177. 1485-1495 (1998)

[Publications] K.Wakabayashi M.Sigrist and M.Fujita: "Spin Wave Mode of Edge-Localized Magnetic States in Nanographite Zigzag Ribbons" J.Phys.Soc.Jpn.167. 2089-2094 (1998)

[Publications] K.Wakabayashi, M.Fujita, H.Ajiki and M.Sigrist.: "Electronic and Magnetic Properties of Nanographite Ribbons" “Phys.Rev.B.April. (1999)

[Publications] M.Igami, M.Fujita, and S.Mizuno: "Edge Localized phonon in Nanogrephite Ribbons" Proceeding of Interntional Conference on Sience and Technology of Synthetic Metals, 1998 Montpellier, France.Synthetic Metals.July. (1999)

[Publications] M.Igami, T.Nakanishi and T.Ando: "Conductance of Carbon Nanotubes with a Vacancy" J.Phys.Soc.Jpn.March. (1999)

[Publications] Y.Takagi, M.Fujita, M.Igami, K.Wakabayashi and K.Nakada: "Electronic Structure and Surface Localized States of Hyper-Graphite Network" Proceeding of International Conference on Sience and Technology of Synthetic Metals, July.1998.Montpellier, France.Synthetic Metals. (1999)

[Publications] K.Nakada, M.Igami and M.Fujita,: "Electron-Electron Interaction in Nanographite Ribbons" J.Phys.Soc.Jpn.vol.67 no.7 1998 pp.2388-2394. 167. 2388-2394 (1998)

[Publications] Y.Miyamoto, K.Nakada and M.Fujita,: "First-principles study on edge state of H-terminated graphitic ribbons," Phys.Rev.B. 59. (1999)

大島忠平早稲田大学, 理工学部, 教授 (10212333)

[Publications] 榎敏明: "新しく炭素材料実験を始める人のために-炭素材料の化学と電子スピン共鳴" 炭素. 181. 44-46 (1998)

[Publications] 榎敏明: "炭素同素体の電子物性と表面" ニューダイヤモンド. 50. 8-12 (1998)