Physical Phenomena in Superconducting Arrays, High-Tc Superconductors, and Composite Media

超导阵列、高温超导体和复合介质中的物理现象

• 批准号: 9731511
• 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: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9731511&HistoricalAwards=false
• 关键词: Physical; Phenomena; Superconducting; Arrays; Tc

9731511 Stroud Theoretical studies will be conducted in three areas of research. The first involves the study of the properties of superconducting arrays. The circumstances under which these arrays can be made to oscillate coherently will be studied by both numerical and analytical techniques. Additional calculations are planned to treat vortex motion, quantum effects, flux noise, a.c. magnetic susceptibility, classical magnetoresistance, and long-range interactions in such arrays, using a variety of theoretical techniques. The second area is a theoretical investigation of flux lattice melting and related phenomena, primarily in high temperature superconductors. A previously developed lowest-Landau level representation will be extended to treat flux lattice melting in the presence of disorder, and to study the behavior of the c-axis Josephson plasmon in the flux liquid state, both with and without disorder. Further calculations of flux lattice melting are planned in a uniformly frustrated XY model and a layered London model, both with and without pinning. As a speculative project, the possibility of extending these approaches to layered magnetic materials will be investigated. Finally, several aspects of the physics of classically inhomogeneous materials will be studied. The emphasis will be on the nonlinear optical response of such materials, and on the linear a.c. response of polycrystals of anisotropic materials (such as quasi-one-dimensional conducting polymers). It is also planned to examine the possibility of treating a disordered two-dimensional superconductor as a model system for chaotic propagation of classical electromagnetic waves. %%% Theoretical research will be conducted in three areas of research using numerical and analytical techniques. These three areas are the study of superconducting arrays; flux lattice melting; and classical inhomogeneous materials. The first two areas are ones which have received increased attention due t o their applicability to the high temperature superconductors. The third area is one of great interest in designing composite materials with unique (optical) properties. ***

9731511 Stroud理论研究将在三个领域进行研究。第一个是研究超导阵列的特性。在何种情况下，这些阵列可以产生相干振荡将通过数值和分析技术进行研究。计划使用各种理论技术来处理涡旋运动、量子效应、磁噪声、交流磁化率、经典磁电阻和这种阵列中的远程相互作用。第二个领域是通量晶格熔化和相关现象的理论研究，主要是在高温超导体中。先前开发的最低朗道水平表示将被扩展到处理无序存在下的通量晶格熔化，并研究c轴约瑟夫森等离子体在有和没有无序的通量液态中的行为。在有钉钉和没有钉钉的情况下，计划在均匀受挫XY模型和分层伦敦模型中进一步计算通量晶格熔化。作为一个推测性项目，将研究将这些方法扩展到层状磁性材料的可能性。最后，将研究经典非均匀材料物理学的几个方面。重点将放在这类材料的非线性光学响应，以及各向异性材料（如准一维导电聚合物）的多晶的线性交流响应。还计划研究将无序二维超导体作为经典电磁波混沌传播的模型系统的可能性。理论研究将在三个研究领域进行，使用数值和分析技术。这三个领域是超导阵列的研究；熔剂点阵熔炼；经典的非均匀材料。前两个领域由于其对高温超导体的适用性而受到越来越多的关注。第三个领域是设计具有独特（光学）性能的复合材料。＊＊＊