SUPERCONDUCTING STATE OF THE LAYERED RUTHENATE

层状钌酸盐的超导态

• 批准号: 09440136
• 负责人: MAENO Yoshiteru
• 金额: $ 8.58万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09440136/
• 关键词: superconductivity; ruthenate; spin triplet superconductivity; SrィイD22ィエD2RuOィイD24ィエD2; specific heat; NMR; p-wave supcrconductivity; anisotropic superconductivity; P波超伝導; 異方的超伝導; 層状酸化物超伝導; アイソトープ効果

The objective of research project is to clarify the superconducting symmetry of SrィイD22ィエD2RuOィイD24ィエD2 mainly through investigation of the specific heat and nuclear magnetic resonance. Through this research project, the quality of the single crystals of SrィイD22ィエD2RuOィイD24ィエD2 has reached an ideal level for most of the investigations.1. As a major achievement of this project, we have demonstrated by nuclear magnetic resonance that superconductivity of SrィイD22ィエD2RuOィイD24ィエD2 is spin triplet.2. We have also provided our crystals to many collaborators, who reported a number of important results. In particular, the observation of spontaneous internal field in the superconducting state by muon spin relaxation indicated that the time-reversal-symmetry is spontaneously broken in the superconducting state, another crucial characteristics of the spin-triplet state specific to SrィイD22ィエD2RuOィイD24ィエD2.3. In addition, we have succeeded in inducing superconducting multiple phases under magnetic fields, characteristic of spin-triplet supcrconductivity.4. Furthermore, we found that the superconducting transition temperature enhances by a factor of two to 3 K in a eutectic mixture of SrィイD22ィエD2RuOィイD24ィエD2 and Ru metal.5. At the same time, detailed theoretical models have been developed in order to describe both the superconducting symmetry and the pairing mechanism of SrィイD22ィエD2RuOィイD24ィエD2.

该研究项目的目标是主要通过比热和核磁共振研究来阐明SrD22D2RuOD24D2的超导对称性。通过该研究项目，Sr D22D2RuOD24D2单晶的质量达到了大多数研究的理想水平。 1. 作为该项目的一项重大成果，我们通过核磁共振证明： SrD22D2RuOD24D2 的超导性是自旋三重态。2． - 对称性在超导态下自发破缺，这是自旋三重态的另一个关键特征SrD22D2RuOD24D2.3此外，我们还成功地在磁场下诱导了超导多相，这是自旋三重态超导的特征。4.此外，我们发现共晶混合物中的超导转变温度提高了2至3K。 SrD22D2RuOD24D2 和 Ru 金属的合成。 5．同时，还开发了详细的理论模型来描述SrD22D2D2RuD24D2的超导对称性和配对机制。

项目成果

Z.Q.Mao: "In-plane Anisotropy of Upper Critical Field in Sr_2RuO_4"Physical Review Letters. 84・5. 991-994 (2000)

毛Z.Q.Mao：“Sr_2RuO_4中的上临界场的面内各向异性”物理评论快报84・5（2000）。

S.Nishizaki: "Changes in the Superconducting State of Sr_2RuO_4 Under Magnetic Fields Probed by Specific Heat."Journal of the Physical Society of Japan. 69・2. 572-578 (2000)

S.Nishizaki：“比热探测下 Sr_2RuO_4 的超导状态的变化”。日本物理学会杂志 69・2（2000 年）。

K. Ishida: "Spin Triplet Superconductivity in SrィイD22ィエD2RuOィイD24ィエD2 Identified by ィイD117ィエD1O Knight Shift"Nature. 396. 658-660 (1998)

K. Ishida：“D117D1O Knight Shift 识别出 SrD22D2RuOD24D2 中的自旋三重态超导性”《自然》396。658-660 (1998)

Y.Maeno: "Experimental Evidence for Spin-Triplet Superconductivity in Sr_2RuO_4"Journal of Superconductivity. 12・4. 535-541 (1999)

Y.Maeno：“Sr_2RuO_4 中自旋三重态超导性的实验证据”超导杂志 12・4（1999）。

H.Mukuda: "Spin Fluctuations in the Ruthenium Oxides RuO_2, SrRuO_3, CaRuO_3, and Sr_2RuO_4 Probed by Ru NMR"Physical Review B. 60・17. 12279-12285 (1999)

H. Mukuda：“通过 Ru NMR 探测的钌氧化物 RuO_2、SrRuO_3、CaRuO_3 和 Sr_2RuO_4 中的自旋波动”物理评论 B. 60・17（1999）。