1994 年度実績報告書

高温超伝導の科学・第4班(超伝導特性班)

研究課題

研究課題/領域番号	04240104
研究機関	東京大学
研究代表者	北沢宏一東京大学, 工学部, 教授 (90011189)
研究分担者	青峰隆文九州大学, 理学部, 教授 (50037206) 松下照男九州工業大学, 情報工学部, 教授 (90038084) 長村光造京都大学, 工学部, 教授 (50026209) 氷上忍東京大学, 教養学部, 教授 (30093298) 小林典男東北大学, 金属材料研究所, 教授 (40111306)
キーワード	超伝導 / 臨界電流 / ピン止め / ボルテックス / 超伝導ゆらぎ / コヒーレンス長 / 臨界磁場
研究概要	高温超伝導体が磁場下におかれ通電された状態における、いわゆる超伝導混合状態を記述するための科学を設立する努力がなされ、以下の成果が得られた。 1.ボルテックスが単独あるいは格子状態で存在する際、高温超伝導のような積層構造でどのような運動状態を呈するかについて、GL方程式を拡張した理論が展開された。 2.高温超伝導特有の超伝導ゆらぎ現象が、電気抵抗と磁化の測定から明らかにされた。また、独特の性質として、ローレンツ力の方向に依存しないエネルギー散逸が詳細に検討された。 3.高温超伝導の磁場-温度に対する相図が作成された。その特徴は従来の上部臨界磁場線が消失し、幅広い超伝導遷移領域が現れることで、物質により大きな差がある。また、不可逆線が現れ、その内部でコヒーレントな状態が出現する。この状態、従来は見られなかった、ボルテックス構造の2次元-3次元転移が生じる。 4.高温超伝導におけるフラックスクリープは、従来超伝導体よりも激しく、その機構は異なっている。精密な測定がなされ、ピンポテンシャルの電流密度依存性などの観点から論じられた。 5.新たな、より高性能の超伝導体を開発する努力がなされ、ピン止め中心を導入する試みとその特性検討がなされた。また、水銀系での新たな組成が見い出され、実用に向けて有望な材料として提示された。ピン止め力を制御する因子が異方性を通して解明され、その化学的改質の指針が得られた。 6.高温超電導体にとって最大の特徴であり、かつ、種々の課題を生みだすもととなっている異方性について詳細な測定が行われ、モデル化がなされた。

研究成果

(36件)

すべてその他

すべて文献書誌 (36件)

[文献書誌] T.Hasegawa, M.Nantoh, et al.: "Atomic Site Tunneling Spectroscopy on High-Tc Superconductors" Physica B. 197. 617-623 (1994)
[文献書誌] Y.Tomioka, M.Nantoh, et al.: "The Meissner and Shielding Effects of High-Temperature Oxide Superconductors" Physica C. 223. 347-360 (1994)
[文献書誌] M.Nantoh, T.Hasegawa. et al.: "Cryogenic STM/STS Observation on Oxide Superconductors" J.Superconductivity. 7(2). 349-353 (1994)
[文献書誌] N.Kobayashi, K.Egawa, et al.: "Fluctuation Effedts in Specific Heat and Magnetization of c-Axis Aligned(Bi,Pb)_2Sr_2Ca_2Cu_3O_X" Physica C. 219. 265-272 (1994)
[文献書誌] S.Kenmochi, H.Iwasaki, and N.Kobayashi: "On Suppression of Superconductivity in the Y_<1-x>Pr_xBa_2Cu_3O_y System" Physica B. 194-196. 2115-2116 (1994)
[文献書誌] H.Iwasaki, O.Taniguchi, et al.: "Resistive Superconducting Transition of Y_<1-x>Pr_xBa_2Cu_3O_y Films in Magnetic Field" Physica B. 194-196. 2117-2118 (1994)
[文献書誌] K.Matsuzaki, A.Inoue, and T.Masumoto: "Oriented Structure and Superconducting Properties in Dense Y_1Ba_2Cu_3 Oxides Prepared by Press Forging" Jpn.J.Appl.Phys.31. L1789-1792 (1992)
[文献書誌] K.Matsuzaki, K.Shimizu, et al.: "Layered Structure and Superconducting Properties of Ag-Sheathed Bi_<1.84>Pb_<0.34>Sr_2Ca_2Cu_3O_y Wire Prepared by Combined Jellyroll and Hotextrusion Technique" Jpn.J.Appl.Phys.33. 1308-1311 (1994)
[文献書誌] K.Watanabe, S.Awaji, et al.: "Characteristics of High Temperature Operation in a Conduction Cooled (Nb,Ti)_3Sn Superconducting Magnet" Adv.Cryo.Eng.40. 847-852 (1994)
[文献書誌] Y.Takane and H.Ebisawa: "Numerical Study on the Conductance of Normal-Superconductor Contacts" Physica B. 194-496. 481-182 (1994)
[文献書誌] K.Tanaka, Y.Takane, et al.: "Application of Cluster Variation Method to Three-Dimensional t-J Model" J.Phys.Soc.Jpn.63. 2909-2918 (1994)
[文献書誌] K.Tanaka, H.Ebisawa, and T.Morita: "Cluster Variation Method for Two-Dimensional Hubbard and t-J Models" Physica C. 235-240. 2187-2188 (1994)
[文献書誌] T.Tamegai, Y.Iye, et al.: "Anormalous Peak Effect in Single Crystal Bi_2Sr_2CaCu_2O_<8+y> Studied by Hall Probe Magnetomertry" Physica C. 213. 33-42 (1993)
[文献書誌] M.Hasegawa, Y.Matsushita, et al.: "Crystal Growth and Resistive Upper Critical Field in Tl_2Ba_2CuO_y and Tl_2Ba_2CaCu_2O_y" Proc.M^2S-HTSC Grenoble. (1994)
[文献書誌] M.Hasegawa, Y.Matsushita, et al.: "Growth and Anisotropic Superconducting Properties of Tl_2Ba_2CuO_y and Tl_2Ba_2CaCu_2O_y Single Crystals" Physica C. 231. 161-166 (1994)
[文献書誌] K.Kishio, D.Pooke, et al.: "Crystal Structure and Anisotropy of Iodine-Intercalated Bi_2Sr_2Ca_<n-1>Cu_nO_x" J.Superconductivity. 7(1). 117-121 (1994)
[文献書誌] D.Pooke, T.Stoto, et al.: "Magnetic and HRTEM Studies of Iodien Intercalated Bi_2Sr_2CaCu_2O_x" OPhysica C. 235-240. 2725-2726 (1994)
[文献書誌] S.Hahakura, J.Shimoyama, et al.: "New Barium-free Mercury-based High-Tc Superconductors:(Hg,Mo)Sr_2(Ca,Y)_<n-1>Cu_nO_y and HgSr_2(Ca,Y)_<n->(Cu,Re)_nO_y(n=1 and 2)" Physica C. 233. 1-7 (1994)
[文献書誌] S.Hikami, M.Shirai, and F.Wegner: "Anderson Localization in the Lowest Landau Level for a Two-Subband Model" Nucl.Phys.B408. 415-426 (1993)
[文献書誌] S.Hikami: "Finite N Analysis of Matrix Models for an n-Ising Spin on a Random Surface" Physica A. 204. 290-305 (1994)
[文献書誌] S.Hikami: "Renormalized Expansions for Matric Models" Prog.Theor.Phys.92. 479-499 (1994)
[文献書誌] K.Osamura, T.Kizu, and T.Oku: "Critical Current Density in YBa_2Cu_3O_<6+x> Added with Perovskite Type Impurity" Physica C. 226. 113-120 (1994)
[文献書誌] K.Osamura, T.Kizu, and T.Oku: "Flux Pinning by Perovskite Type Impurity in YBa_2Cu_3O_<6+x>" Adv.in Cryog.Eng.40. 71-78 (1994)
[文献書誌] K.Osamura, M.Kamo, et al.: "Influence of Sausaging Effect on V-1 Characteristics of Ag Sheathed Bi2223 Tapes" Cryogenics. 34. 303-308 (1994)
[文献書誌] Y.Horie, T.Hamamoto, et al.: "Ultrasonic Studies of Crystal Structure Dependence of Flux Pinning in Bi_2Sr_2Ca_<n-1>Cu_nO_y(n=1,2 and 3)" Physica B. 194-196. 1581-1582 (1994)
[文献書誌] T.Aomine, T.Nishizaki, et al.: "Temperature and Magnetic Field-Direction Dependence of Transport Critical Currents in Single-Crystalline Thin Films of YBa_2Cu_3O_<7-δ>" Physica B. 194-196. 1613-1614 (1994)
[文献書誌] T.Fukami, D.Lee, et al.: "Magnetic Field-Direction Dependence of Criticl Current Density in c-axis Oriented Bi_2Sr_<1.7>La_<0.3>CuO_<6+v> Films" Physica B. 194-196. 1835-1836 (1994)
[文献書誌] T.Matsushita, E.S.Otabe, et al.: "Anisotropy of Irreversibility Line in a Superconducting Bi-2223 Tape Wire" Adv. Cryo. Engng.40. 33-40 (1994)
[文献書誌] T.Matsushita: "Elastic Moduli of Fluxoid Lattice in Tape-II Superconductors, Local or Nonlocal" Physica C. 220. 172-180 (1994)
[文献書誌] T.Matsushita: "Flux Bundle Size in Weakly Pinned Superconductors" Adv.in Superconductivity. VI. 503-506 (1994)
[文献書誌] T.Yokota, T.Takahashi, et al.: "Anomalous Band-folding Due to The BiO Superstructure in Bi_2Sr_2CaCu_2O_8 Studied by Angle-Resolved Photoemission" Phys.Rev.B50. 10225 (1994)
[文献書誌] K.Kadowaki, T.Mochiku, et al.: "Non-Linear Transport Phenomena along The c-Axis in Single Crystalline Bi_2Sr_2CaCu_2O_<8+δ>" Physica C. 235-240. 3275-3276 (1994)
[文献書誌] K.Matsuzaki, A.Inoue, and T.Masumoto: "High Temperature Superconducting Electronics" オーム社, 11 (1993)
[文献書誌] S.Awaji, K.Watanabe, et al.: "Adv.in Superconductivity VI" Springer-Verlag, 4 (1994)
[文献書誌] K.Watanabe, S.Awaji, et al.: "Critical Currents in Superconductors" World Scientific, 6 (1994)
[文献書誌] K.Kadowaki, S.L.Yuan, and K.Kitazawa: "Superconductor Sci.and Technol." IOP, 22 (1994)

1994 年度 実績報告書

高温超伝導の科学・第4班(超伝導特性班)

研究代表者

北沢 宏一 東京大学, 工学部, 教授 (90011189)

研究成果

[文献書誌] T.Hasegawa, M.Nantoh, et al.: "Atomic Site Tunneling Spectroscopy on High-Tc Superconductors" Physica B. 197. 617-623 (1994)

[文献書誌] Y.Tomioka, M.Nantoh, et al.: "The Meissner and Shielding Effects of High-Temperature Oxide Superconductors" Physica C. 223. 347-360 (1994)

[文献書誌] M.Nantoh, T.Hasegawa. et al.: "Cryogenic STM/STS Observation on Oxide Superconductors" J.Superconductivity. 7(2). 349-353 (1994)

[文献書誌] N.Kobayashi, K.Egawa, et al.: "Fluctuation Effedts in Specific Heat and Magnetization of c-Axis Aligned(Bi,Pb)_2Sr_2Ca_2Cu_3O_X" Physica C. 219. 265-272 (1994)

[文献書誌] S.Kenmochi, H.Iwasaki, and N.Kobayashi: "On Suppression of Superconductivity in the Y_<1-x>Pr_xBa_2Cu_3O_y System" Physica B. 194-196. 2115-2116 (1994)

[文献書誌] H.Iwasaki, O.Taniguchi, et al.: "Resistive Superconducting Transition of Y_<1-x>Pr_xBa_2Cu_3O_y Films in Magnetic Field" Physica B. 194-196. 2117-2118 (1994)

[文献書誌] K.Matsuzaki, A.Inoue, and T.Masumoto: "Oriented Structure and Superconducting Properties in Dense Y_1Ba_2Cu_3 Oxides Prepared by Press Forging" Jpn.J.Appl.Phys.31. L1789-1792 (1992)

[文献書誌] K.Matsuzaki, K.Shimizu, et al.: "Layered Structure and Superconducting Properties of Ag-Sheathed Bi_<1.84>Pb_<0.34>Sr_2Ca_2Cu_3O_y Wire Prepared by Combined Jellyroll and Hotextrusion Technique" Jpn.J.Appl.Phys.33. 1308-1311 (1994)

[文献書誌] K.Watanabe, S.Awaji, et al.: "Characteristics of High Temperature Operation in a Conduction Cooled (Nb,Ti)_3Sn Superconducting Magnet" Adv.Cryo.Eng.40. 847-852 (1994)

[文献書誌] Y.Takane and H.Ebisawa: "Numerical Study on the Conductance of Normal-Superconductor Contacts" Physica B. 194-496. 481-182 (1994)

[文献書誌] K.Tanaka, Y.Takane, et al.: "Application of Cluster Variation Method to Three-Dimensional t-J Model" J.Phys.Soc.Jpn.63. 2909-2918 (1994)

[文献書誌] K.Tanaka, H.Ebisawa, and T.Morita: "Cluster Variation Method for Two-Dimensional Hubbard and t-J Models" Physica C. 235-240. 2187-2188 (1994)

[文献書誌] T.Tamegai, Y.Iye, et al.: "Anormalous Peak Effect in Single Crystal Bi_2Sr_2CaCu_2O_<8+y> Studied by Hall Probe Magnetomertry" Physica C. 213. 33-42 (1993)

[文献書誌] M.Hasegawa, Y.Matsushita, et al.: "Crystal Growth and Resistive Upper Critical Field in Tl_2Ba_2CuO_y and Tl_2Ba_2CaCu_2O_y" Proc.M^2S-HTSC Grenoble. (1994)

[文献書誌] M.Hasegawa, Y.Matsushita, et al.: "Growth and Anisotropic Superconducting Properties of Tl_2Ba_2CuO_y and Tl_2Ba_2CaCu_2O_y Single Crystals" Physica C. 231. 161-166 (1994)

[文献書誌] K.Kishio, D.Pooke, et al.: "Crystal Structure and Anisotropy of Iodine-Intercalated Bi_2Sr_2Ca_<n-1>Cu_nO_x" J.Superconductivity. 7(1). 117-121 (1994)

[文献書誌] D.Pooke, T.Stoto, et al.: "Magnetic and HRTEM Studies of Iodien Intercalated Bi_2Sr_2CaCu_2O_x" OPhysica C. 235-240. 2725-2726 (1994)

[文献書誌] S.Hahakura, J.Shimoyama, et al.: "New Barium-free Mercury-based High-Tc Superconductors:(Hg,Mo)Sr_2(Ca,Y)_<n-1>Cu_nO_y and HgSr_2(Ca,Y)_<n->(Cu,Re)_nO_y(n=1 and 2)" Physica C. 233. 1-7 (1994)

[文献書誌] S.Hikami, M.Shirai, and F.Wegner: "Anderson Localization in the Lowest Landau Level for a Two-Subband Model" Nucl.Phys.B408. 415-426 (1993)

[文献書誌] S.Hikami: "Finite N Analysis of Matrix Models for an n-Ising Spin on a Random Surface" Physica A. 204. 290-305 (1994)

[文献書誌] S.Hikami: "Renormalized Expansions for Matric Models" Prog.Theor.Phys.92. 479-499 (1994)

[文献書誌] K.Osamura, T.Kizu, and T.Oku: "Critical Current Density in YBa_2Cu_3O_<6+x> Added with Perovskite Type Impurity" Physica C. 226. 113-120 (1994)

[文献書誌] K.Osamura, T.Kizu, and T.Oku: "Flux Pinning by Perovskite Type Impurity in YBa_2Cu_3O_<6+x>" Adv.in Cryog.Eng.40. 71-78 (1994)

[文献書誌] K.Osamura, M.Kamo, et al.: "Influence of Sausaging Effect on V-1 Characteristics of Ag Sheathed Bi2223 Tapes" Cryogenics. 34. 303-308 (1994)

[文献書誌] Y.Horie, T.Hamamoto, et al.: "Ultrasonic Studies of Crystal Structure Dependence of Flux Pinning in Bi_2Sr_2Ca_<n-1>Cu_nO_y(n=1,2 and 3)" Physica B. 194-196. 1581-1582 (1994)

[文献書誌] T.Aomine, T.Nishizaki, et al.: "Temperature and Magnetic Field-Direction Dependence of Transport Critical Currents in Single-Crystalline Thin Films of YBa_2Cu_3O_<7-δ>" Physica B. 194-196. 1613-1614 (1994)

[文献書誌] T.Fukami, D.Lee, et al.: "Magnetic Field-Direction Dependence of Criticl Current Density in c-axis Oriented Bi_2Sr_<1.7>La_<0.3>CuO_<6+v> Films" Physica B. 194-196. 1835-1836 (1994)

[文献書誌] T.Matsushita, E.S.Otabe, et al.: "Anisotropy of Irreversibility Line in a Superconducting Bi-2223 Tape Wire" Adv. Cryo. Engng.40. 33-40 (1994)

[文献書誌] T.Matsushita: "Elastic Moduli of Fluxoid Lattice in Tape-II Superconductors, Local or Nonlocal" Physica C. 220. 172-180 (1994)

[文献書誌] T.Matsushita: "Flux Bundle Size in Weakly Pinned Superconductors" Adv.in Superconductivity. VI. 503-506 (1994)

[文献書誌] T.Yokota, T.Takahashi, et al.: "Anomalous Band-folding Due to The BiO Superstructure in Bi_2Sr_2CaCu_2O_8 Studied by Angle-Resolved Photoemission" Phys.Rev.B50. 10225 (1994)

[文献書誌] K.Kadowaki, T.Mochiku, et al.: "Non-Linear Transport Phenomena along The c-Axis in Single Crystalline Bi_2Sr_2CaCu_2O_<8+δ>" Physica C. 235-240. 3275-3276 (1994)

[文献書誌] K.Matsuzaki, A.Inoue, and T.Masumoto: "High Temperature Superconducting Electronics" オーム社, 11 (1993)

[文献書誌] S.Awaji, K.Watanabe, et al.: "Adv.in Superconductivity VI" Springer-Verlag, 4 (1994)

[文献書誌] K.Watanabe, S.Awaji, et al.: "Critical Currents in Superconductors" World Scientific, 6 (1994)

[文献書誌] K.Kadowaki, S.L.Yuan, and K.Kitazawa: "Superconductor Sci.and Technol." IOP, 22 (1994)

1994 年度実績報告書

北沢宏一東京大学, 工学部, 教授 (90011189)