Collaborative Research: Imaging of Vortex Phases in Artificially Structured Superconductors

这个合作实验凝聚态物理学项目探讨了超导体中空间调制态的静态和动态相位的基本物理学。 重点关注该领域的两个重要问题：强磁场对量子隧道现象的作用，以及人为约束几何形状中超导体中磁场诱导缺陷的动态行为。 这项工作的一个重点是使用扫描霍尔探针显微镜对调制超导状态进行直接空间成像，这种技术允许非侵入性地映射超导和磁性结构上方的局部磁场。 该项目是一个合作的努力，涉及两名研究人员在磁性和超导性方面的互补专业知识。 该项目的一个核心部分是对研究生和本科生进行物理和材料研究技术方面的培训。 他们将培养的技能将使他们在未来的各种职业道路上为国家的科学基础做出贡献。本项目将研究超导领域的两个重要问题。 在整个项目中使用的关键技术是扫描霍尔探针显微镜，它允许非侵入性地映射超导和磁性结构上方的局部磁场。 在第一项研究中，将研究强磁场对两个超导体之间电子隧穿的作用。 这种在大磁场中隧穿的物理学目前只被部分理解。 霍尔显微镜在这项研究中将是一个特别强大的工具，因为它可以直接对流动的超电流进行成像。 在调查的第二个领域，霍尔显微镜将被用来成像的静态和动态行为的涡旋在超导体已被结构化使用微米和纳米光刻技术。 其中一个待研究的例子是一种新型的“涡旋棘轮”，其中涡旋可以以精确控制的步骤移动。 这种棘轮可能在高精度计量中有可能的应用。 该项目的一个核心部分是对研究生和本科生进行物理和材料研究技术方面的培训。他们将发展的技能将使他们能够在未来的各种职业道路上为国家的科学基础做出贡献。

This collaborative experimental condensed matter physics project explores the fundamental physics of static and dynamic phases of spatially modulated states in superconductors. The focus is on two important problems in this area: the role of strong magnetic fields on quantum tunneling phenomena, and the dynamic behavior of magnetic field-induced defects in superconductors in artificially constrained geometries. One emphasis of the work is on direct spatial imaging of modulated superconducting states using scanning Hall probe microscopy, a technique that allows non-invasive mapping of the local magnetic field above superconducting and magnetic structures. This project is a collaborative effort involving two investigators with complementary expertise in magnetism and superconductivity. A central part of the project is the training of both graduate and undergraduate students in physics and materials research techniques. The skills they will develop will position them to contribute to the nation's scientific base in a variety of future career paths.This project will investigate two important problems in the field of superconductivity. A key technique used throughout the project is that of scanning Hall probe microscopy, which allows non-invasive mapping of the local magnetic field above superconducting and magnetic structures. In the first study, the role of strong magnetic fields on the tunneling of electrons between two superconductors will be investigated. The physics of this tunneling in large fields is currently only partly understood. The Hall microscope will be particularly a powerful tool in this study, as it allows for the direct imaging of the flowing supercurrents. In the second area of investigation, the Hall microscope will be used to image the static and dynamic behavior of vortices in superconductors that have been structured using micro- and nano-lithographic techniques. One such example to be studied is a novel "vortex ratchet", in which vortices can be moved in precisely controlled steps. This ratchet may have possible applications in high-precision metrology. A central part of the project is the training of both graduate and undergraduate students in physics and materials research techniques. The skills they will develop will position them to contribute to the nation's scientific base in a variety of future career paths.