Study of the Superconducting Proximity Effect of Cu-Nb systems with Magnetic Impurities and Application for the New Superconducting Wire.

磁性杂质Cu-Nb系超导邻近效应研究及新型超导线材应用。

• 批准号: 63840008
• 负责人: ODA Yasukage
• 金额: $ 3.39万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63840008/
• 关键词: Superconducting Proximity Effect; Meissner Effect; Cooper Pairs; Energy Gap; N M R; Low Temperature; New Superconducting Material; マイスナー効果; クーパー対の侵入

1. The Meissner effect of Cu clad Nb wire samples with magnetic impurities such as Fe, Co, Ni and Mn has been studied. The measurements was done over the temperature range of 10mK-10K by means of the a.c. method. The large depairing effect due to the Kondo's effect was observed in Cu with these magnetic impurities. The Meissner region, P, was found to be proportional to T^<-1/2> over the temperature range. The result implies that the probability of the spin-flip scattering by the s-d exchange interaction is almost unchanged over the temperature range. Recently, Narikiyo and Fukuyama have calculated the temperature dependence of P. They indicate that P increases below Kondo's temperature T_K as decreasing temperature. Our results are not consistent with the calculation.The Cu clad wire with magnetic impurities is under further investigation for application, in order to develop new materials for the superconducting wires.2. The NMR study was carried out of the Cu and Nb thin multi-layers. From the measurements of the nuclear spin lattice relaxation time, T_1, of Cu nuclei, the superconducting energy gas was found to be induced by the proximity effect. Both superconducting and normal electrons were found to coexist in Cu as our expectation.

1.研究了含Fe、Co、Ni、Mn等磁性杂质的铜包Nb线材样品的迈斯纳效应。用交流测温仪在10mK-10K温度范围内进行了测量。方法。在含有这些磁性杂质的铜中，观察到了由于近藤效应而产生的大的脱偶效应。在温度范围内，迈斯纳区域P与T^lt；-1/2成比例。结果表明，在此温度范围内，S-d交换相互作用产生自旋-翻转散射的几率几乎不变。最近，Narikiyo和Fukuyama计算了P的温度依赖性，他们指出，P在近藤温度T_K以下随着温度的降低而增加。我们的结果与计算结果并不一致，含磁性杂质的铜包线正在进一步研究应用，以开发用于超导线材的新材料。对铜和Nb薄多层膜进行了核磁共振研究。测量了铜原子核的自旋晶格驰豫时间T_1，发现超导能气是由邻近效应引起的。正如我们所预期的那样，在铜中同时存在超导电子和正常电子。

项目成果

鄭国慶 他6名: "NMR Study of the Proximity Effect in Nb-Cu Multilayers" Journal of the Physical Society of Japan. 58-1. 39-42 (1989)

郑国庆等6人：“Nb-Cu多层膜中邻近效应的NMR研究”日本物理学会杂志58-1 39-42（1989）。

青木亮三 他5名: "^<63> Cu NMR Study of Superconducting Cu/Nb Multilayer-Film" Journal of the Physical Society of Japan. 56,12. 4495-4502 (1987)

Ryozo Aoki 等 5 人：“超导 Cu/Nb 多层膜的 ^ 63 Cu NMR 研究”，日本物理学会杂志 56，12 4495-4502（1987 年）。

R. Aoki, G.Q. Zheng, Y. Kohori, Y. Oda, K. Asayama, S. Wada: "^<63>Cu NMR Study of Superconducting Cu/Nb Multilayer-Film" J. Phys. Soc. Jpn. Vol.56, No.12 (1987) pp.4495-4502.

R.青木，G.Q.

Guo-qing Zheng;Y.Kohori;Y.Oda;K.Asayama;R.Aoki;Y.Obi;H.Fujimori: J.Plrsp.Soc.Jpn.58. 39-42 (1989)

郑国庆；Y.Kohori；Y.Oda；K.Asayama；R.Aoki；Y.Obi；H.Fujimori：J.Plrsp.Soc.Jpn.58。

H. Toyoda, T. Kaneko, Y. Oda, K. Asayama: "The Meissner Effect of Cu Clad Nb Wires with Magnetic Impurities" J. Phys. Soc. Jpn.

H. Toyoda、T. Kaneko、Y. Oda、K. Asayama：“含磁性杂质的铜包铌线的迈斯纳效应”J. Phys。