1996 Fiscal Year Annual Research Report

高濃度酸素ドープによる高温超伝導薄膜の大面積・高速成膜法の開発

Research Project

Project/Area Number	08750373
Research Institution	Kyushu University
Principal Investigator	木須隆暢九州大学, 大学院・システム情報科学研究科, 助教授 (00221911)
Keywords	高温超伝導 / YBaCuO / 薄膜 / レーザアブレーション / 磁束ピンニング / 電流電圧特性 / 臨界電流 / パーコレーション
Research Abstract	1.レーザアブレーションによる高品質YBaCuO超伝導薄膜の作製エキシマレーザならびにYAGレーザの4倍高調波を用いたレーザアブレーションの実験を行い、基板温度、ガス圧、ガス流量、ターゲット基板間距離、レーザ出力、基板材料等の条件が膜質に及ぼす影響について詳細に調べた。その結果、条件を最適化することで、SrTiO_3,LaAlO_3,MgO基板上に高品質YBaCuO薄膜を得た。得られた膜の臨界温度(T_c)、および77K 零磁場中での臨界電流密度(J_c)はそれぞれ、T_c=92K,J_c=4-5×10^6A/cm^2(SrTiO_3);T_c=90K,J_c=1×10^6A/cm^2(LaAlO_3);T_c=88K,J_c=5×10^5A/cm^2(MgO)である。また、YBaCuO超伝導層/SrTiO_3絶縁層/YBaCuO超伝導層の多層構造の作製条件を確立した。得られた膜の超伝導特性をさらに詳細に調べるため、実用上重要となると考えられる次の2点について重点的に実験を行った。 2.YBaCuO薄膜の磁束ピン止め特性の評価超伝導体の磁束ピン止め特性の解明は、高電流密度化、磁束雑音の低減、電流-電圧特性の理論表式の導出など、実用上極めて重要となる。上述した薄膜を用い、電流-電圧特性の温度・磁場依存性を10桁以上の広い電界領域に亘って詳細に計測し、理論的考察を加えることによって、臨界電流の統計的局所分布を明らかにすると共に、輸送特性の温度・磁場依存性を定量的に記述する理論表式の導出に成功した。 3.YBaCuO薄膜のマイクロ波特性の評価移動体通信用の高周波素子として需要が期待される YBaCuO高温超伝導薄膜の高周波損失、磁場侵入長等、高周波領域における基礎的パラメータの測定を行った。

Research Products
(19 results)

All Other

All Publications (19 results)

[Publications] Takanobu Kiss: "Laser Deposition of Y_1Ba_2Cu_3O_<7-δ>-SrTiO_3-Y_1Ba_2Cu_3O_<7-δ> Multilayers Utilizing the 4th Harmonics of Nd : YAG Pulse Laser" ICEC Transactions on Electronics. E79-C・9. 1269-1273 (1996)
[Publications] Takanobu Kiss: "Transport Characteristics in High T_c Superconductors with Pin Fluctuation under the Influence of Thermal Agitation" Proc. 8th Int. Workshop on Critical Currents in Superconductors. 39-44 (1996)
[Publications] Takanobu Kiss: "Pin Fluctuation and The Scaling of Transport Characteristics in Superconductors" Czech Journal of Physics. 46・S3. 1719-1720 (1996)
[Publications] Takanobu Kiss: "The Relationship between Pin Distribution and Scaling Behavior in High Tc Superconductor" Advences in Superconductivity VIII. 8. 469-472 (1996)
[Publications] Takanobu Kiss: "Flux Flow Characteristics of Step-Edge Junctions Made of Y1B2Cu307-δ Thin Films" Superconductor Science and Technology. 9・4A. 148-151 (1996)
[Publications] 木須隆暢: "高温超伝導体の磁束融解相転移と磁束ピンニング" 超伝導ニュース. 26. 20-21 (1996)
[Publications] Kaoru Yamafuji: "A New Interpretation on The Glass-Liquid Transition of Pinned Fluxoids in High-Tc Superconductors" Physica C. 258・3-4. 197-212 (1996)
[Publications] 山藤馨: "高温超伝導体における磁束ピンニング" 応用物理. 65・4. 350-355 (1996)
[Publications] 吉田啓二: "高温超伝導Y-Ba-Cu-O薄膜の磁場侵入長の評価" 九州大学工学集報. 69・1. 83-88 (1996)
[Publications] 吉田啓二: "超伝導Y-Ba-Cu薄膜の残留表面抵抗の評価" 九州大学工学集報. 69・2. 176-180 (1996)
[Publications] Keiji Yoshida: "Weakly coulped grain model for the resudual surfae resistance of Y_1Ba_2Cu_3O_<7-δ> thin films" ICEC Transactions on Electronics. E79-C・9. 1254-1259 (1996)
[Publications] Takanobu Kiss: "Transport Characteristics and flux dynamics in high Tc superconductors in the presence of pin fluctation" IEEE Trans. 1996 Applied Superconduictivity Conf.6(印刷中). (1997)
[Publications] Keiji Yoshida: "Residual surface registance of YBa_2Cu_3O_x thin films-Weakly coupled grain model" IEEE Trans. 1996 Applied Superconduictivity Conf.6(印刷中). (1997)
[Publications] Takanobu Kiss: "Estimation of dynamic transport properties in high Tc superconductors based on the percolative partial flux flow model" Proc. 9th Int.Sympo.Superconductivity. (印刷中). (1997)
[Publications] Kaoru Yamafuji: "Generalized critical state model in high-Tc superconductors" Proc.U.S.-Japan Workshop in High Field Superconductiong Materials and Standards. (印刷中). (1997)
[Publications] Takanobu Kiss: "DC and AC transport properties if high Tc superconductors" Proc. U.S.-Japan Workshop in High Field Superconductiong Materials and Standards. (印刷中). (1997)
[Publications] Kaoru Yamafuji: "Generalized critical state model in high Tc superconductors" Physida C. (印刷中). (1997)
[Publications] Takanobu Kiss: "On the scaling of transport characteristics in high T_c superconductors from the view point of pin-fluctuation" Proc.ICEC16/ICMC 5. (印刷中). (1997)
[Publications] Taketsune Nakamura: "Temperature and magentic-field scaling of transport characteristics in high quality Y_1Ba_2Cu_3O_<7-δ> thin films" Proc.ICEC16/ICMC 5. (印刷中). (1997)

1996 Fiscal Year Annual Research Report

高濃度酸素ドープによる高温超伝導薄膜の大面積・高速成膜法の開発

Principal Investigator

木須 隆暢 九州大学, 大学院・システム情報科学研究科, 助教授 (00221911)

Research Products

[Publications] Takanobu Kiss: "Laser Deposition of Y_1Ba_2Cu_3O_<7-δ>-SrTiO_3-Y_1Ba_2Cu_3O_<7-δ> Multilayers Utilizing the 4th Harmonics of Nd : YAG Pulse Laser" ICEC Transactions on Electronics. E79-C・9. 1269-1273 (1996)

[Publications] Takanobu Kiss: "Transport Characteristics in High T_c Superconductors with Pin Fluctuation under the Influence of Thermal Agitation" Proc. 8th Int. Workshop on Critical Currents in Superconductors. 39-44 (1996)

[Publications] Takanobu Kiss: "Pin Fluctuation and The Scaling of Transport Characteristics in Superconductors" Czech Journal of Physics. 46・S3. 1719-1720 (1996)

[Publications] Takanobu Kiss: "The Relationship between Pin Distribution and Scaling Behavior in High Tc Superconductor" Advences in Superconductivity VIII. 8. 469-472 (1996)

[Publications] Takanobu Kiss: "Flux Flow Characteristics of Step-Edge Junctions Made of Y1B2Cu307-δ Thin Films" Superconductor Science and Technology. 9・4A. 148-151 (1996)

[Publications] 木須隆暢: "高温超伝導体の磁束融解相転移と磁束ピンニング" 超伝導ニュース. 26. 20-21 (1996)

[Publications] Kaoru Yamafuji: "A New Interpretation on The Glass-Liquid Transition of Pinned Fluxoids in High-Tc Superconductors" Physica C. 258・3-4. 197-212 (1996)

[Publications] 山藤馨: "高温超伝導体における磁束ピンニング" 応用物理. 65・4. 350-355 (1996)

[Publications] 吉田啓二: "高温超伝導Y-Ba-Cu-O薄膜の磁場侵入長の評価" 九州大学工学集報. 69・1. 83-88 (1996)

[Publications] 吉田啓二: "超伝導Y-Ba-Cu薄膜の残留表面抵抗の評価" 九州大学工学集報. 69・2. 176-180 (1996)

[Publications] Keiji Yoshida: "Weakly coulped grain model for the resudual surfae resistance of Y_1Ba_2Cu_3O_<7-δ> thin films" ICEC Transactions on Electronics. E79-C・9. 1254-1259 (1996)

[Publications] Takanobu Kiss: "Transport Characteristics and flux dynamics in high Tc superconductors in the presence of pin fluctation" IEEE Trans. 1996 Applied Superconduictivity Conf.6(印刷中). (1997)

[Publications] Keiji Yoshida: "Residual surface registance of YBa_2Cu_3O_x thin films-Weakly coupled grain model" IEEE Trans. 1996 Applied Superconduictivity Conf.6(印刷中). (1997)

[Publications] Takanobu Kiss: "Estimation of dynamic transport properties in high Tc superconductors based on the percolative partial flux flow model" Proc. 9th Int.Sympo.Superconductivity. (印刷中). (1997)

[Publications] Kaoru Yamafuji: "Generalized critical state model in high-Tc superconductors" Proc.U.S.-Japan Workshop in High Field Superconductiong Materials and Standards. (印刷中). (1997)

[Publications] Takanobu Kiss: "DC and AC transport properties if high Tc superconductors" Proc. U.S.-Japan Workshop in High Field Superconductiong Materials and Standards. (印刷中). (1997)

[Publications] Kaoru Yamafuji: "Generalized critical state model in high Tc superconductors" Physida C. (印刷中). (1997)

[Publications] Takanobu Kiss: "On the scaling of transport characteristics in high T_c superconductors from the view point of pin-fluctuation" Proc.ICEC16/ICMC 5. (印刷中). (1997)

[Publications] Taketsune Nakamura: "Temperature and magentic-field scaling of transport characteristics in high quality Y_1Ba_2Cu_3O_<7-δ> thin films" Proc.ICEC16/ICMC 5. (印刷中). (1997)

木須隆暢九州大学, 大学院・システム情報科学研究科, 助教授 (00221911)