Theoretical Studies of Josephson Arrays, High-Temperature Superconductors, and Inhomogeneous Media

约瑟夫森阵列、高温超导体和非均匀介质的理论研究

• 批准号: 0104987
• 负责人: David Stroud
• 金额: --
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0104987&HistoricalAwards=false
• 关键词: Theoretical; Studies; Josephson; Arrays; Temperature

0104987StroudTheoretical research will be conducted in three areas of materials research: (1) the physics of superconducting arrays and related materials: (2) fluctuations and inhomogeneities in cuprate-based high temperature superconductors; (3) linear and nonlinear response of macroscopically inhomogeneous materials. Superconducting arrays are arrangements of superconductors which are weakly coupled together by Josephson or proximity-effect interactions. They have a wide variety of potential applications and are also good models for superconducting thin films. In this area continued study of underdamped Josephson arrays coupled to a resonant cavity will be carried out. In addition, a study of noise produced by magnetic flux motion in arrays and films will also be undertaken, as well as a study of conditions under which a superconducting array can lock into a coherent state. Finally, a study will be made of quantum effects in superconducting arrays, films and smaller groups of junctions. Models for terahertz absorption in the underdoped high temperature superconducting materials will be studied. Also to be investigated are models of low-angle grain boundaries in the ab-planes of the high temperature superconductors, since grain boundaries limit the critical current. The c-axis current-voltage characteristics of these materials will also be investigated, as well as the conditions governing the position and width of the Josephson plasmon resonance in the most anisotropic materials. Also, recent calculations o fquantum melting of the vortex lattice at zero temperature will be compared to experiment. The PI will also extend recent work on macroscopically inhomogeneous media to the study of magnetic composites. Here the problems to be addressed include magnetoresistance arising from the inhomogeneous conductivity tensor in a material with a ferromagnetic domain structure, and the behavior of magnetic multilayers coupled through nonmagnetic layers, which will be studied by a model analogous to the Lawrence-Doniach treatment of layered superconductors. Finally, the PI will study the electromagnetic response of collections of small metal and dielectric particles contained in an optical microcavity.The research involves studies of several fundamental questions in condensed matter physics, and may lead to a wide variety of technological applications. It will also contribute to human resources in science and technology by training graduate students and postdoctoral fellows.%%%Theoretical research will be conducted in three areas of materials research: (1) the physics of superconducting arrays and related materials: (2) fluctuations and inhomogeneities in cuprate-based high temperature superconductors; (3) linear and nonlinear response of macroscopically inhomogeneous materials. The research involves studies of several fundamental questions in condensed matter physics, and may lead to a wide variety of technological applications. It will also contribute to human resources in science and technology by training graduate students and postdoctoral fellows.***

0104987将在材料研究的三个领域进行：（1）超导阵列和相关材料的物理学：（2）基于丘陵的高温超导体的波动和不均匀性； （3）宏观不均匀材料的线性和非线性响应。 超导阵列是超导体的排列，它们通过约瑟夫森或接近效应的相互作用薄弱地耦合在一起。 它们具有多种潜在的应用，也是超导薄膜的良好模型。 在这一领域，将继续研究与偶联的约瑟夫森阵列不足的约瑟夫森阵列。 此外，还将进行对阵列和膜中磁通运动产生的噪声的研究，以及对超导阵列可以锁定到连贯状态的条件的研究。 最后，将研究超导阵列，薄膜和较小的连接组中的量子效应。 将研究低温高温超导材料吸收的Terahertz吸收模型。 还需要研究的是高温超导体的AB-范围中低角度晶界的模型，因为晶界限制了临界电流。 还将研究这些材料的C轴电流特性，以及在最各向异性材料中控制约瑟夫森等离子体共振的位置和宽度的条件。 同样，将最新的计算在零温度下的涡旋晶格熔融与实验进行比较。 PI还将将宏观不均匀培养基的最新工作扩展到磁复合材料的研究。 在这里，要解决的问题包括由具有铁磁域结构的材料中的不均匀电导率张量引起的磁性，以及通过非磁性层耦合的磁性多层的行为，这将由类似于Lawrence-Donioch处理的模型来研究超导体。 最后，PI将研究光学微腔内包含的小金属和介电颗粒的集合的电磁反应。该研究涉及对凝聚态物理学中几个基本问​​题的研究，并可能导致多种技术应用。 它还将通过培训研究生和博士后研究员来为科学和技术的人力资源做出贡献。%%％理论研究将在材料研究的三个领域进行：（1）超导阵列和相关材料的物理学：（2）波动。和基于铜矿的高温超导体的不均匀性； （3）宏观不均匀材料的线性和非线性响应。 该研究涉及对凝结物理学的几个基本问​​题的研究，并可能导致多种技术应用。 它还将通过培训研究生和博士后研究员为科学和技术的人力资源做出贡献。***