激光诱导超导薄膜钉扎中心机理研究

目前我国对第二代钇系高温超导材料的研究和应用已取得长足进展，但还面临着带材生产成本偏高、效率偏低等较多难题。为此，以激光CVD增强技术为突破口，提出创建“超导层(GdBa2Cu3O7-x)/模板层（GdBa2Cu3O7-x+掺杂元素Ce）”新型双层复合薄膜结构的构想，着重研究激光诱导下钉扎中心形成、转移的起因、过程和机制。研究内容包括：模板层的构建依据；激光诱导下模板层中掺杂元素原子取代位转变为超导层钉扎中心形成点的过程、原因和机制；超导层中钉扎中心对其在高场下临界电流密度、磁通钉扎力的影响规律及机制。通过以上研究，以期建立激光诱导下模板层构建的理论依据，并确定模板层中的掺杂元素浓度对超导层中的缺陷类型、缺陷密度的影响规律和机制，同时可探明激光诱导下超导层制备工艺参数对其在高场下临界电流密度、磁通钉扎力的影响规律和机制。本研究可为制备高性能、低成本的新型复合超导带材提供理论依据和技术支持。

Although great progress on the second generation superconducting tape had been made in China, a number of problems such as relatively low fabrication efficiency and high fabrication cost still needed to be cracked. Aiming to these problems, an innovative solution of a double-layered structure of GdBa2Cu3O7-x/ (GdBa2Cu3O7-x + Ce) prepared by laser CVD was proposed. The origin, processing and mechanism for formation and transfer of the pinning center would be investigated with a special emphasis. For instance, the construction principle and selection rule for the template layer, the processing and mechanism for the transformation under inducing of laser photos from the doping element spot to superconducting pinning center; the principle and mechanism of the effects of the pinning center on the critical current density (JC) and magnetic flux force (FP). By the present research, theory for preparing the template layer under inducing of laser photos could be developed, and principle as well as mechanism of the effects of doping-element concentration on the type and density of defects could be illustrated; at the same time, mechanism of the effects of preparation parameters of the superconducting layer on the JC and Fp could be revealed. The present research could be a theory and technology support for fabrication of cost effective superconducting tape with high electrical performances.