Tunneling and Transport in Ordered and Disordered Superconductors

有序和无序超导体中的隧道效应和输运

• 批准号: 9623477
• 负责人: Allen Goldman
• 金额: $ 39万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-04-01 至 1999-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9623477&HistoricalAwards=false
• 关键词: Tunneling; Transport; Ordered; Disordered; Superconductors

9623477 Goldman The study of two dimensional superconducting films allows access to several important paradigms in contemporary Condensed Matter Physics including the superconductor-insulator transition, the quantum tunneling of vortices, and other quantum properties of Abrikosov vortices. The hallmark of the work is the extension of the parameter space to very low temperatures and very high magnetic fields. The focus of work on the superconductor-insulator transition will be on resolving whether the transition is governed by a variant of the Boson- Hubbard model or, is a consequence of decreased screening by disorder of the repulsive electron-electron interaction. The work on quantum tunneling of vortices should reveal new features of the dynamics of vortices, in particular the extent to which their behavior can be fundamentally quantum mechanical. The other investigations of quantum properties of vortices, including studies of quantum vortex lattice melting, superconducting analogs of the quantum Hall effect, and vortex shot noise will contribute to a coherent picture of electron transport and superconductivity in two dimensions. %%% The study of two dimensional superconductors impacts important paradigms in contemporary Condensed Matter Physics including the superconductor-insulator transition, and the quantum tunneling of vortices, an important dynamical property of Abrikosov vortices. The investigation of model problems and model systems in two dimensions, in addition to their intrinsic scientific interest, will contribute to our knowledge of the mechanism of high-Tc superconductivity, and to our understanding of vortex dynamics. The dynamics of vortices, which exist in superconductors in magnetic fields, are of interest because vortex motion causes dissipation. The promise of superconductivity to bring about changes in electrical and electronic technology is connect ed with reduced dissipation. The understanding of the mechanism of high temperature superconductivity will aid in the search for new materials. The understanding of the fundamental limits on performance resulting from vortex motion will contribute to our understanding of factors which could limit the technological usefulness of superconductors. ***

9623477戈德曼对二维超导薄膜的研究使我们能够接触到当代凝聚态物理中的几个重要范例，包括超导体-绝缘体转变、涡旋的量子隧道以及阿布里科索夫涡旋的其他量子性质。这项工作的特点是将参数空间扩展到很低的温度和很高的磁场。超导体-绝缘体转变的工作重点将是解决这种转变是由玻色子-哈伯德模型的变体控制的，还是由于排斥电子相互作用的无序而导致屏蔽减少的结果。关于涡旋的量子隧道的工作应该揭示涡旋动力学的新特征，特别是它们的行为从根本上可以是量子力学的程度。其他对涡旋量子性质的研究，包括量子涡旋晶格熔化的研究、量子霍尔效应的超导类比以及涡旋散粒噪声的研究，将有助于在两个维度上形成电子输运和超导的相干图像。二维超导体的研究影响了当代凝聚态物理中的重要范式，包括超导体-绝缘体转变和涡旋的量子隧穿，涡旋是Abrikosov涡旋的一个重要的动力学性质。对二维模型问题和模型系统的研究，除了它们固有的科学意义外，还将有助于我们了解高温超导的机制，以及我们对涡旋动力学的理解。存在于磁场中的超导体中的涡旋的动力学是令人感兴趣的，因为涡旋运动引起了耗散。超导性带来电气和电子技术变革的前景与降低损耗有关。对高温超导机理的理解将有助于寻找新的材料。了解涡旋运动对性能的基本限制将有助于我们理解可能限制超导体技术用途的因素。***