1992 Fiscal Year Annual Research Report

高温超伝導の科学・第4班(超伝導特性班)

Research Project

Project/Area Number	04240104
Research Institution	The University of Tokyo
Principal Investigator	北沢宏一東京大学, 工学部, 教授 (90011189)
Co-Investigator(Kenkyū-buntansha)	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, 助教授 (30093298) 小林典男東北大学, 金属材料研究所, 教授 (40111306)
Keywords	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
Research Abstract	本分野は超伝導研究の中で唯一、我国が他国に全体として水を空けられている分野である。しかしながらいくつかのユニークな研究が展開されており、本班の組識化によって全体としての研究レベルの向上と、ユニークな研究の進展をはかるのが目的であった。その意味で本班のまず最大の業績は組識化された努力によって、超伝導現象論の学問分野が我国の研究者の中に根付きはじめたことである。第2の点として、我国の研究から提唱され始めた超伝導ゆらぎの現象が根本的には全世界に受け容れられ、それが理論的にも実験的にも深められつつある状況となった。このような観点から、磁界と電流、結晶構造の相対角度を精密制御する測定によりユニークで、かつ、良質単結晶を用いて、より定量的な研究がなされた。またこのゆらぎ領域を記述する理論の展開が行われ、いくつかの物理量を予言するに至っている。一方、このようなゆらぎ領域と抵抗がゼロとなる領域との境界は不可逆線と呼ばれるようになり、高温超伝導体の異方性との関連を注目する研究がいくつか行われるようになった。一方、抵抗がゼロとなる不可逆領域内でも、熱活性化によるクリープ現象が観測される。これは実用上も大変に重要な現象であり、多くの研究例があるが、本研究ではそのための新しいアプローチがいくつかなされるようになった。その例は、ホール素子を使用しての実験やあるいは磁歪を利用してのユニークなものである。コヒーレンス及び磁気侵入に関する研究にSTMやマイクロ波測定が適用され、独自の方法として結果が出されている。これらはまだいずれも充分深まったとはいえないが、新しいアプローチとして今後の発展を期待してよいと考えられる。

Research Products
(33 results)

All Other

All Publications (33 results)

[Publications] K.Kitazawa: "Studies on Anisotropy of Oxide Superconductors by STM/STS and Magnetization Measurements" JJAP Series. 7. 253-259 (1992)
[Publications] T.Hasegawa: "Atomic Site Tunneling Spectroscopy on Oxide Superconductors" J.Phys.Chem.Solids. 53. 1643-1650 (1992)
[Publications] J.Li: "Growth and Properties of Pure C_<60> Single Crystals from Vapor" Physica. C195. 205-208 (1992)
[Publications] N.Kobayashi: "Study of Resistive Superconducting Transition in YBa_2 Cu_3 O_7 Films" Sci.Rep.Res.Inst.Tohoku Univ.A. 37. 143-150 (1992)
[Publications] K.Watanabe: "Polycrystalline Y_1 Ba_2 Cu_3 O_<7-> Films Prepared by CVD Method" Advances in Cryogenic Engineering(Materials). 38. 991-996 (1992)
[Publications] S.Awaji: "Dimensional Crossover Effect in J_C Characteristics of Chemical Vapor Deposition Processed YBa_2 Cu_3 O_<7-> Films" Jpn.J.Appl.Phys.31. 1532-1535 (1992)
[Publications] K.Matsuzaki: "High-Tc superconducting properties and structure of T1-Ba-Ca-Cu oxide wires produced through hot extrusion" Material Letters. 13. 368-372 (1992)
[Publications] Y.Takane: "Conductance Formula for Mesoscopic Systems with a Superconducting Segment" J.Phys.Soc.Jpn.61. 1685-1690 (1992)
[Publications] Y.Takane: "Conductance and Its Fluctuations of Mesoscopic Wires in Contact with a Superconductor" J.Phys.Soc.Japan. 61. 2858-2864 (1992)
[Publications] Y.Takane: "Conductance of Normal-Superconductor Contacts Due to the Andreev Reflection" J.Phys.Soc.Jpn.61. 3466-3469 (1992)
[Publications] K.Kishio: "Anisotropic Magnetization,Flux Pinning and Critical Current Density of La-Sr-Cu-O Single Crystal" Supercond.Sci.Technol.5(1S). S69-S72 (1992)
[Publications] T.Kimura: "Compositional Dependence of Transport Anisotropy in Large(La,Sr)_2 CuO_4 Single Crystals and Second Peak in Magnetization Curves" Physica. C192. 247-252 (1992)
[Publications] N.Chikumoto: "Temperature Dependence of the Lower Critical Field under the Effect of Surface Barriers in Bi_2 Sr_2 CaCu_2 O_8 Crystal" Physica. C199. 32-36 (1992)
[Publications] T.Matsuda: "Superconduting Fluctuation in the Hall Conductivity:An Estimation of Skew-Scattering Life Time in YBa_2 Cu_3 O_<7->" Physical Review. B45. 4901-4906 (1992)
[Publications] Y.Iye: "Anisotropy of Bi_2 Sr_2 CaCu_2 O_<8+y> Revisited" Physica. C199. 154-160 (1992)
[Publications] Y.Iye: "How Anisotropic Are the Layered Cuprate High Tc Superconductors?" Mat.Phys.16. 89-111 (1992)
[Publications] Y.Iye: "Doping-,Pressure and Temperature-Depencences of the Hall Coefficients in High Tc Cuprates" Phys.Chem.Solids. 53. 1561-1568 (1992)
[Publications] K.Osamura: "Work Instability and its Influence to Critical Current Density of Ag Sheathed Bi2223 Tapes" Superconductor Sci.Technol.5. 1-6 (1992)
[Publications] K.Osamura: "Microstructure Control and Critical Current Density of Ag Sheathed Bi2223 Tapes" Adv.in Superconductivity. 4. 565-568 (1992)
[Publications] W.Zhang: "Phase Equilibria at Low Oxygen Partial Pressuer in Y-Ba-Cu-O System" Physica C. 190. 396-402 (1992)
[Publications] K.Osamura: "Fracture Behavior and Critical Current Density of Ag Sheathed High T_C Superconducting Tapes" Adv.in Cryo.Eng.38. 875-881 (1992)
[Publications] T.Fukami: "Critical Current and Activation Energy Due to Two Dimensional Layered Structure in Ba_2 Sr_2 CaCu_2 O_<8+y> Film" Helvetica Physica Acta. 65. 115-116 (1992)
[Publications] T.Fukami: "Preparation of (Bi_<1-X>Pb_X)_2 Sr_2 Ca_2 Cu_3 O_<10> Films by RF-Sputtering with Compound Powder Target of Stoichiometric Composition" Helvetica Physica Acta. 65. 117-118 (1992)
[Publications] T.Matsusita: "Effect of Coherence Lingth in the C-Axis on Irreversibility Properties in Anisotropic High Temperature Superconductors" Adv.Superconductivity. (1993)
[Publications] T.Matsusita: "Flux Creep in the Vicinity of Irreversibility Lines" Adv.Superconductivity. (1993)
[Publications] T.Matsusita: "Effect of Short Coherence Length along the C-Axis on Irreversibility Line in High T_C Superconductors" Physica C. (1993)
[Publications] H.Obara: "Zero-Field-Cooled,Field-Cooled and Remanent Magnetization of Epitaxial YBCO Films" ¨Advanced in Superconductivity ¨Springer-Verlag Tokyo. 759-762 (1992)
[Publications] A.Sawa: "Role of Ozone in the Oxidation of YBCO Thin Films'" ¨Advanced in Superconductivity ¨Spreinger-Verlag Tokyo. 659-662 (1992)
[Publications] M.Suzuki: "Thermally Activated Resistive Behavior and Flux Motion in La_<2-X> Sr_X CuO_4 Single-Crystal Thin Films" Phys.Rev.B. 46. 14230-14233 (1992)
[Publications] M.Suzuki: "Fluctuation Conductivity and Normal Resistivity in La_<2-X> Sr_X CuO_4 as a Function of Doping" Phys.Rev.B. 47. (1993)
[Publications] M.Murakami: "Flux Pinning by Non-Superconducting Inclusions in Melt-Processed YBaCuO Superconductors" Cryogenics. 32. 930-935 (1992)
[Publications] 小原春彦: "酸化物超電導薄膜の磁化特性" 電子技術総合研究所, 120 (1993)
[Publications] M.Murakami: "Melt Processed High-Temperature Superconductors" World Scientific, 361 (1993)

1992 Fiscal Year Annual Research Report

高温超伝導の科学・第4班(超伝導特性班)

Principal Investigator

北沢 宏一 東京大学, 工学部, 教授 (90011189)

Research Products

[Publications] K.Kitazawa: "Studies on Anisotropy of Oxide Superconductors by STM/STS and Magnetization Measurements" JJAP Series. 7. 253-259 (1992)

[Publications] T.Hasegawa: "Atomic Site Tunneling Spectroscopy on Oxide Superconductors" J.Phys.Chem.Solids. 53. 1643-1650 (1992)

[Publications] J.Li: "Growth and Properties of Pure C_<60> Single Crystals from Vapor" Physica. C195. 205-208 (1992)

[Publications] N.Kobayashi: "Study of Resistive Superconducting Transition in YBa_2 Cu_3 O_7 Films" Sci.Rep.Res.Inst.Tohoku Univ.A. 37. 143-150 (1992)

[Publications] K.Watanabe: "Polycrystalline Y_1 Ba_2 Cu_3 O_<7-> Films Prepared by CVD Method" Advances in Cryogenic Engineering(Materials). 38. 991-996 (1992)

[Publications] S.Awaji: "Dimensional Crossover Effect in J_C Characteristics of Chemical Vapor Deposition Processed YBa_2 Cu_3 O_<7-> Films" Jpn.J.Appl.Phys.31. 1532-1535 (1992)

[Publications] K.Matsuzaki: "High-Tc superconducting properties and structure of T1-Ba-Ca-Cu oxide wires produced through hot extrusion" Material Letters. 13. 368-372 (1992)

[Publications] Y.Takane: "Conductance Formula for Mesoscopic Systems with a Superconducting Segment" J.Phys.Soc.Jpn.61. 1685-1690 (1992)

[Publications] Y.Takane: "Conductance and Its Fluctuations of Mesoscopic Wires in Contact with a Superconductor" J.Phys.Soc.Japan. 61. 2858-2864 (1992)

[Publications] Y.Takane: "Conductance of Normal-Superconductor Contacts Due to the Andreev Reflection" J.Phys.Soc.Jpn.61. 3466-3469 (1992)

[Publications] K.Kishio: "Anisotropic Magnetization,Flux Pinning and Critical Current Density of La-Sr-Cu-O Single Crystal" Supercond.Sci.Technol.5(1S). S69-S72 (1992)

[Publications] T.Kimura: "Compositional Dependence of Transport Anisotropy in Large(La,Sr)_2 CuO_4 Single Crystals and Second Peak in Magnetization Curves" Physica. C192. 247-252 (1992)

[Publications] N.Chikumoto: "Temperature Dependence of the Lower Critical Field under the Effect of Surface Barriers in Bi_2 Sr_2 CaCu_2 O_8 Crystal" Physica. C199. 32-36 (1992)

[Publications] T.Matsuda: "Superconduting Fluctuation in the Hall Conductivity:An Estimation of Skew-Scattering Life Time in YBa_2 Cu_3 O_<7->" Physical Review. B45. 4901-4906 (1992)

[Publications] Y.Iye: "Anisotropy of Bi_2 Sr_2 CaCu_2 O_<8+y> Revisited" Physica. C199. 154-160 (1992)

[Publications] Y.Iye: "How Anisotropic Are the Layered Cuprate High Tc Superconductors?" Mat.Phys.16. 89-111 (1992)

[Publications] Y.Iye: "Doping-,Pressure and Temperature-Depencences of the Hall Coefficients in High Tc Cuprates" Phys.Chem.Solids. 53. 1561-1568 (1992)

[Publications] K.Osamura: "Work Instability and its Influence to Critical Current Density of Ag Sheathed Bi2223 Tapes" Superconductor Sci.Technol.5. 1-6 (1992)

[Publications] K.Osamura: "Microstructure Control and Critical Current Density of Ag Sheathed Bi2223 Tapes" Adv.in Superconductivity. 4. 565-568 (1992)

[Publications] W.Zhang: "Phase Equilibria at Low Oxygen Partial Pressuer in Y-Ba-Cu-O System" Physica C. 190. 396-402 (1992)

[Publications] K.Osamura: "Fracture Behavior and Critical Current Density of Ag Sheathed High T_C Superconducting Tapes" Adv.in Cryo.Eng.38. 875-881 (1992)

[Publications] T.Fukami: "Critical Current and Activation Energy Due to Two Dimensional Layered Structure in Ba_2 Sr_2 CaCu_2 O_<8+y> Film" Helvetica Physica Acta. 65. 115-116 (1992)

[Publications] T.Fukami: "Preparation of (Bi_<1-X>Pb_X)_2 Sr_2 Ca_2 Cu_3 O_<10> Films by RF-Sputtering with Compound Powder Target of Stoichiometric Composition" Helvetica Physica Acta. 65. 117-118 (1992)

[Publications] T.Matsusita: "Effect of Coherence Lingth in the C-Axis on Irreversibility Properties in Anisotropic High Temperature Superconductors" Adv.Superconductivity. (1993)

[Publications] T.Matsusita: "Flux Creep in the Vicinity of Irreversibility Lines" Adv.Superconductivity. (1993)

[Publications] T.Matsusita: "Effect of Short Coherence Length along the C-Axis on Irreversibility Line in High T_C Superconductors" Physica C. (1993)

[Publications] H.Obara: "Zero-Field-Cooled,Field-Cooled and Remanent Magnetization of Epitaxial YBCO Films" ¨Advanced in Superconductivity ¨Springer-Verlag Tokyo. 759-762 (1992)

[Publications] A.Sawa: "Role of Ozone in the Oxidation of YBCO Thin Films'" ¨Advanced in Superconductivity ¨Spreinger-Verlag Tokyo. 659-662 (1992)

[Publications] M.Suzuki: "Thermally Activated Resistive Behavior and Flux Motion in La_<2-X> Sr_X CuO_4 Single-Crystal Thin Films" Phys.Rev.B. 46. 14230-14233 (1992)

[Publications] M.Suzuki: "Fluctuation Conductivity and Normal Resistivity in La_<2-X> Sr_X CuO_4 as a Function of Doping" Phys.Rev.B. 47. (1993)

[Publications] M.Murakami: "Flux Pinning by Non-Superconducting Inclusions in Melt-Processed YBaCuO Superconductors" Cryogenics. 32. 930-935 (1992)

[Publications] 小原 春彦: "酸化物超電導薄膜の磁化特性" 電子技術総合研究所, 120 (1993)

[Publications] M.Murakami: "Melt Processed High-Temperature Superconductors" World Scientific, 361 (1993)

北沢宏一東京大学, 工学部, 教授 (90011189)

[Publications] 小原春彦: "酸化物超電導薄膜の磁化特性" 電子技術総合研究所, 120 (1993)