ORDER-PARAMETER SYMMETRY OF HIGH-T_cSUPERCONDUCTORS BY MEANS OF BULK PHYSICAL QUANTITY

高温超导体的大体积物理量的有序参数对称性

• 批准号: 08454100
• 负责人: ISHIDA Takekazu
• 金额: $ 4.99万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08454100/
• 关键词: torque magnetometer; high-T_C superconductivity; order-parameter symmetry; YBa_2Cu_3O_7

The order parameter symmetry of high-T_0 superconductors has been investigated by means of the bulk physical quantity. This is in contrast with that many experiments were carried out on the basis of surface properties. We built a new torque magnetometer using a split-type 6-T superconducting magnet. The measurement program has been coded using HP-BASIC.The in-plane torque of an untwinned YBa_2Cu_3O_7 single crystal consists of two-fold and four-fold symmetries. The former comes from the mass anisotropy between m_a and m_b. The latter is related with the order parameter symmetry, and is consistent with the existing theories. Our results are not compatible with the d_<xy> symmetry but are in good accordance with the d_<x^2-y^2> symmetry. We consider that our findings are convincing because the magnetic torque reflects information over the whole crystal.

用体物理量方法研究了高T_0超导体的序参量对称性。这与许多实验是基于表面性质进行的形成了鲜明对比。我们用分离式6-T超导磁体建造了一台新的扭矩磁强计。用HP-BASIC语言编制了测量程序。未孪晶YBa2Cu3O7单晶的面内扭矩由两重和四重对称性组成。前者来自于ma和mb之间的质量各向异性，后者与序参数对称性有关，与已有的理论一致。我们的结果与d_&lt；xy&gt；对称性不相容，但与d_&lt；x^2-y^2&gt；对称性符合得很好。我们认为我们的发现是令人信服的，因为磁矩反映了整个晶体上的信息。

项目成果

T.ISHIDA et al.: "Vortex Lattice Melting in Untuinred ・・・" Advauces in Supercon duetinty. Vol.X. 457-460 (1998)

T.ISHIDA 等人：“Untuinred 中的涡旋晶格熔化...”Advauces in Supercon duetinty（第 X 卷）。

T.Mikayama, T.Ishida et al.: "Kim Critical State in Twinned YBa_2Cu_3O_7 Single Crystal." Advanced in Superconductivity. Vol.VIII (Springer-Verlag). 571-574 (1996)

T.Mikayama、T.Ishida 等人：“孪晶 YBa_2Cu_3O_7 单晶中的 Kim 临界态”。

T.Ishida et al.: "Vortex lattice melting in untwinned single crystal YBa_2Cu_3O_7 when field are applied parallel to CuO_2 plane." Advances in Superconductivity. X (in press). (1998)

T.Ishida 等人：“当场平行于 CuO_2 平面施加时，非孪晶单晶 YBa_2Cu_3O_7 中的涡旋晶格熔化。”

T.Ishida et al.: "Matching Effect between the Density of Screw Dislocations and the Break Field in the Irreversibility Lines of YBa_2Cu_3O_<7-delta> Films." Physica C. 266. 1-10 (1996)

T.Ishida 等人：“YBa_2Cu_3O_<7-delta> 薄膜的不可逆线中螺旋位错密度与断裂场之间的匹配效应”。

T.Ishida et al.: "Vortex Lattice Melting in Untwinned Single Crystal YBa_2Cu_3O_7 when Fields are Applied Parallel to CuO_2 Plane." Advanced in Superconductivity. Vol.X (Springer-Verlag, 1998). 457-460

T.Ishida 等人：“当场平行于 CuO_2 平面时，非孪晶单晶 YBa_2Cu_3O_7 中的涡旋晶格熔化。”