1992 Fiscal Year Annual Research Report

高温超伝導の科学:総括班

Research Project

Project/Area Number	04240101
Research Institution	Tohoku University
Principal Investigator	立木昌東北大学, 金属材料研究所, 教授 (20028111)
Co-Investigator(Kenkyū-buntansha)	藤田敏三広島大学, 理学部, 教授 (20004369) 北沢宏一東京大学, 工学部, 教授 (90011189) 佐藤正俊名古屋大学, 理学部, 教授 (40092225) 坂東尚周京都大学, 化学研究所, 教授 (70027027) 福山秀敏東京大学, 理学部, 教授 (10004441)
Keywords	高温超伝導 / ニュースレター / ミニ研究会 / 磁気励起 / 単結晶 / 国際交流
Research Abstract	本総括班は、重点領域研究「高温超伝導の科学」の各班の活発な研究活動を促すとともに、プロジェクト研究としての目標達成のために、次のような活動を行った。特に、総括班主導の重点課題研究の推進と、重要テーマに焦点を絞ったブレーンストーミング的なミニ研究会の開催を2本の柱にして、本領域の研究の基本的な方向付けを行ってきた。 (1)総括班会議を4回開催:年間スケジュールの決定、各班の活動の把握、国内外の研究に関する情報収集、その他領域運営に関する問題点の点検と把握、(2)ニュースレターの発行(2回):1号-各班の研究方針、研究組織表と連絡先(住所録)、研究開始状況、その他連絡事項。2号-ミニ研究会の報告を中心にした活動状況(3)重点課題の研究促進:本年度は次の4テーマに絞って、総括班が中心となって研究環境の整備を行い研究の促進を図った。(1)良質な担結晶資料の作成(兒嶋担当)、(2)NMRによる高温超伝導体の磁気励起の研究(安岡担当)、(3)高温超伝導体における巨大磁歪の異方性測定(北沢担当)、(4)新超伝導体探索のための磁化測定(庄野担当)、(5)酸化物高温超伝導体の混合状態の異常を解明するためのシミュレーション(立木担当)、(4)ミニ研究会開催:総括班主催のトピックス別ミニ研究会を8回開催し、実質的な討論を行った。他にA02班・A05班合同、A01班、A03班などの各班別の合宿形式研究会をサポートした(5)研究成果発表会:1月11〜13日に野口英世記念開館(東京)において、公開で研究発表会を開催し、計95件の報告があった。(6)研究連絡網の強化:総括班メンバーを中心に連絡を密にするとともに、仙台〜広島間のデータ転送コンピュータネットを整備した。(7)国際研究交流:個別交流の他、「強相関系の日露ワークショップ」(堺、12月)に総括班から2名を派遣し、情報交換を行った。

Research Products
(27 results)

All Other

All Publications (27 results)

[Publications] M.Tachiki: "Effect of intrinsic pinning on critical current in cuprate superconductors" Cryogenics. 32. 923-930 (1992)
[Publications] M.Tachiki: "Superconducting properties of layered cuprate oxides" Prog.Theor.Phys.Suppl.108. 297-311 (1992)
[Publications] M.Sasaki: "Electronic states of high-Tc cuprate superconductors as studied by the use of the composite-operator approach" Phys.Rev.B. 46. 3022-3040 (1992)
[Publications] T.Tanamoto: "Fermi surface and spin fluctuations in extended t-J model" J.Phys.Soc.Japan. 61. 1886-1890 (1992)
[Publications] T.Tanamoto: "Magnetic properties of extended t-J model. I. Static properties" J.Phys.Soc.Japan. 62. 717-730 (1993)
[Publications] H.Fukuyama: "On magnetic properties of high Tc oxides" Prog.Theor.Phys.Suppl.108. 287-295 (1992)
[Publications] M.Azuma: "Superconductivity at 110k in the infinite-layer compound (Sr_<1-x>Ca_x)_<1-y>CuO_2" Nature. 356. 775-776 (1992)
[Publications] Y.Matsuda: "Disappcarance of hall resistance in one-unit-cell-thick YBa_2Cu_3O_<7-δ> Evidence of free vortex-antivortex excitation" Phys.Rev.Left.69. 3228-3231 (1992)
[Publications] T.Nishizaki: "Lorentz-force dependence of transport critical currents anisotropic pinning properties in YBa_2Cu_3O_<7-δ> single-crystalline thin films" Physica C. 204. 305-314 (1993)
[Publications] M.Sato: "Magnetic excitations in superocnducting YBa_2Cu_3O_<6+x> crystals studied by neutron inelastic scattering" J.Phys.Soc.Jpn.62. 263-273 (1993)
[Publications] M.Sera: "Substitution effects on the thermoelectric power of La_<2-x>Sr_xCu_<1-y>M_yO_4(M=Z_n and Ni)and YBa_2Cu_<3-y>Zn_yO_<7-δ>" J.Phys.Soc.Jpn. 62. 281-288 (1993)
[Publications] T.Nishikawa: "Hole density dependence of the low temperature electronic specific heat coefficient of La_<2-x>Sr_xCaCu_2O_6 with weakly localized electrons" Physica C.
[Publications] T.Hasegawa: "Atomic site tunneling spectroscopy on oxide superconductors" J.Phys.Chem.Solids. 53. 1643-1650 (1992)
[Publications] H.Ikuta: "Giant magnetostriciton in Bi_2Sr_2CaCu_<>O_8 single crystal in the superconducting state and its mechanism" Phys.Rev.Lett.
[Publications] T.Nagano: "Bulk superconductivity in both tetragonal and orthorhombic solid solutions of (La_<1-x>Sr_x)_2Cu)_4" Phys.Rev.B.
[Publications] T.Kusumori: "Fabrication of YBCO/CeO_2/YBCO multilayer junctions and their characteristics" Jpn.J.Appl.Phys.31. L956-L959 (1992)
[Publications] I.Iguchi: "Tunnel-like characteristics of YBa_2Cu_3O_<7-y>/CeO_2/YBa_2Cu_3O_<7-y> junctions and possible evidence of excitations responsible for high-Tc superconductivity" Phys.Rev.B. 46. 11175-11178 (1992)
[Publications] I.Iguchi: "Tunnel,Josephson and proximity effects in high Tc multilayers" Proceeding of Beijing International Conference on High Tc superocnductivity(BHTSC'92).
[Publications] Y.Maeno: "Instability at 1/8 doping in La_<2-x>Ba_xCuO_4 and related compounds" Jpn.J.Appl.Phys.Series 7. 7. 91-98 (1992)
[Publications] T.Fujita: "Ultrasonic study on anisotropic elastic properties of oxide superconductors" J.Advanced Science. 4. 131-134 (1992)
[Publications] M.Lang: "Lattice instabilities in cuprate superconductors : A possible limitting mechanism for Tc" Phys.Rev.Lett.69. 482-485 (1992)
[Publications] Y.Sakaguchi: "Shock-loading effects on flux pinning of the high Tc superconductor La_<1.85>Sr_<0.15>CuO_4" Physica C. 201. 183-188 (1992)
[Publications] H.Yamaguchi: "X-ray absorption study of PbBaSrYCuO_<7+δ> and PbBaSr (Y,Ca)Cu_2O_<7+δ>" Ferroelectrics. 128. 191-196 (1992)
[Publications] Y.Muraoka: "Structural and superconducting properties of iodine in tercalated Bi_2Sr_2Ca_<1-x>Y_xCu_2O_z" Physica C. 204. 65-70 (1993)
[Publications] Y.Tokura: "Filling dependence of electronic properties on the verge of metal-Mott insulator transition in Sr_<1-x>La_xTiO_3" Phys.Rev.Lett.
[Publications] T.Arima: "Optical spectra of Pr_<2-x>Ce_xCuO_<4-δ> crystals: Evolution of ingap states with electron-doping" Phys.Rev.B.
[Publications] T.Katsufuji: "Symmetry-dependent electronic Raman scattering in La_<2-x>Sr_xCuO_4: Evidence for doping-induced change in K-space anisotropy of charge dynamics" Phys.Rev.Lett.

1992 Fiscal Year Annual Research Report

高温超伝導の科学:総括班

Principal Investigator

立木 昌 東北大学, 金属材料研究所, 教授 (20028111)

Research Products

[Publications] M.Tachiki: "Effect of intrinsic pinning on critical current in cuprate superconductors" Cryogenics. 32. 923-930 (1992)

[Publications] M.Tachiki: "Superconducting properties of layered cuprate oxides" Prog.Theor.Phys.Suppl.108. 297-311 (1992)

[Publications] M.Sasaki: "Electronic states of high-Tc cuprate superconductors as studied by the use of the composite-operator approach" Phys.Rev.B. 46. 3022-3040 (1992)

[Publications] T.Tanamoto: "Fermi surface and spin fluctuations in extended t-J model" J.Phys.Soc.Japan. 61. 1886-1890 (1992)

[Publications] T.Tanamoto: "Magnetic properties of extended t-J model. I. Static properties" J.Phys.Soc.Japan. 62. 717-730 (1993)

[Publications] H.Fukuyama: "On magnetic properties of high Tc oxides" Prog.Theor.Phys.Suppl.108. 287-295 (1992)

[Publications] M.Azuma: "Superconductivity at 110k in the infinite-layer compound (Sr_<1-x>Ca_x)_<1-y>CuO_2" Nature. 356. 775-776 (1992)

[Publications] Y.Matsuda: "Disappcarance of hall resistance in one-unit-cell-thick YBa_2Cu_3O_<7-δ> Evidence of free vortex-antivortex excitation" Phys.Rev.Left.69. 3228-3231 (1992)

[Publications] T.Nishizaki: "Lorentz-force dependence of transport critical currents anisotropic pinning properties in YBa_2Cu_3O_<7-δ> single-crystalline thin films" Physica C. 204. 305-314 (1993)

[Publications] M.Sato: "Magnetic excitations in superocnducting YBa_2Cu_3O_<6+x> crystals studied by neutron inelastic scattering" J.Phys.Soc.Jpn.62. 263-273 (1993)

[Publications] M.Sera: "Substitution effects on the thermoelectric power of La_<2-x>Sr_xCu_<1-y>M_yO_4(M=Z_n and Ni)and YBa_2Cu_<3-y>Zn_yO_<7-δ>" J.Phys.Soc.Jpn. 62. 281-288 (1993)

[Publications] T.Nishikawa: "Hole density dependence of the low temperature electronic specific heat coefficient of La_<2-x>Sr_xCaCu_2O_6 with weakly localized electrons" Physica C.

[Publications] T.Hasegawa: "Atomic site tunneling spectroscopy on oxide superconductors" J.Phys.Chem.Solids. 53. 1643-1650 (1992)

[Publications] H.Ikuta: "Giant magnetostriciton in Bi_2Sr_2CaCu_<>O_8 single crystal in the superconducting state and its mechanism" Phys.Rev.Lett.

[Publications] T.Nagano: "Bulk superconductivity in both tetragonal and orthorhombic solid solutions of (La_<1-x>Sr_x)_2Cu)_4" Phys.Rev.B.

[Publications] T.Kusumori: "Fabrication of YBCO/CeO_2/YBCO multilayer junctions and their characteristics" Jpn.J.Appl.Phys.31. L956-L959 (1992)

[Publications] I.Iguchi: "Tunnel-like characteristics of YBa_2Cu_3O_<7-y>/CeO_2/YBa_2Cu_3O_<7-y> junctions and possible evidence of excitations responsible for high-Tc superconductivity" Phys.Rev.B. 46. 11175-11178 (1992)

[Publications] I.Iguchi: "Tunnel,Josephson and proximity effects in high Tc multilayers" Proceeding of Beijing International Conference on High Tc superocnductivity(BHTSC'92).

[Publications] Y.Maeno: "Instability at 1/8 doping in La_<2-x>Ba_xCuO_4 and related compounds" Jpn.J.Appl.Phys.Series 7. 7. 91-98 (1992)

[Publications] T.Fujita: "Ultrasonic study on anisotropic elastic properties of oxide superconductors" J.Advanced Science. 4. 131-134 (1992)

[Publications] M.Lang: "Lattice instabilities in cuprate superconductors : A possible limitting mechanism for Tc" Phys.Rev.Lett.69. 482-485 (1992)

[Publications] Y.Sakaguchi: "Shock-loading effects on flux pinning of the high Tc superconductor La_<1.85>Sr_<0.15>CuO_4" Physica C. 201. 183-188 (1992)

[Publications] H.Yamaguchi: "X-ray absorption study of PbBaSrYCuO_<7+δ> and PbBaSr (Y,Ca)Cu_2O_<7+δ>" Ferroelectrics. 128. 191-196 (1992)

[Publications] Y.Muraoka: "Structural and superconducting properties of iodine in tercalated Bi_2Sr_2Ca_<1-x>Y_xCu_2O_z" Physica C. 204. 65-70 (1993)

[Publications] Y.Tokura: "Filling dependence of electronic properties on the verge of metal-Mott insulator transition in Sr_<1-x>La_xTiO_3" Phys.Rev.Lett.

[Publications] T.Arima: "Optical spectra of Pr_<2-x>Ce_xCuO_<4-δ> crystals: Evolution of ingap states with electron-doping" Phys.Rev.B.

[Publications] T.Katsufuji: "Symmetry-dependent electronic Raman scattering in La_<2-x>Sr_xCuO_4: Evidence for doping-induced change in K-space anisotropy of charge dynamics" Phys.Rev.Lett.

立木昌東北大学, 金属材料研究所, 教授 (20028111)