Spectroscopic Properties of Two-Dimensional Superconductors

非技术摘要：超导体是固体物质的特殊状态。了解是什么使固体超导是物理学研究的一个宏伟目标，在新兴的量子通信和计算领域很有用。最近，在层状范德华材料中发现了一些新的超导体，这些材料本质上是结晶的。但是超导性的机制以及超导态对观测性质的影响仍然是未知的。在这个项目中，扫描隧道显微镜将被用来在原子尺度上了解这些新材料的量子力学性质。在这个项目中进行的研究将被用于开发高中和本科教育的新模块。该项目还将为高中以上的学生提供科学和技术教育机会。技术摘要：二维超导仍然是凝聚态物理的知识前沿，在理解配对机制和涨落及其对观察到的光谱和输运性质的影响方面存在基本的开放问题。最近，创造晶态二维超导体成为可能，这种超导体只有几个单位晶胞厚。其中包括机械剥离的块状超导体，如二硒化铌，以及新出现的超导体，如扭曲的双层石墨烯。这个项目将使用扫描隧道显微镜和光谱学来洞察这些新的超导体类别中的局域态密度。干涉实验将用于深入了解超导带隙的对称性和结构。在外加磁场中的测量也将被用来洞察这些材料中的涡旋运动和波动，这些材料通常处于干净的极限，其中平均自由程远远大于涡旋的大小。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical Abstract: Superconductors are special states of solid matter. Understanding what makes solids superconducting is a grand goal of physics research, useful in the emerging fields of quantum communication and computation. Recently, a number of new superconductors have been discovered in layered van der Waals materials that are crystalline in nature. But the mechanisms of superconductivity and the consequences of the superconducting state to the observed properties are still unknown. In this project, scanning tunneling microscopy will be used to understand the quantum mechanical properties of these new classes of materials at the atomic scale. Research performed in this project will be used to develop new modules for high school and undergraduate education. The project will also provide science and technical education opportunities for students at levels from high school upwards.Technical Abstract: Superconductivity in two dimensions remains an intellectual frontier in condensed matter physics with fundamental open problems in understanding pairing mechanisms and fluctuations and their consequences for the observed spectroscopic and transport properties. Recently, it has become possible to create crystalline two-dimensional superconductors that are only a few unit cells thick. These include mechanically exfoliated bulk superconductors such as niobium diselenide as well as new emergent superconductors such as twisted bilayer graphene. This project will use scanning tunneling microscopy and spectroscopy to gain insight into the local density of states in these new classes of superconductors. Interference experiments will be used to gain insight into the symmetry and structure of superconducting gaps. Measurements in applied magnetic fields will also be used to gain insight into vortex motion and fluctuations in these materials which can often be in the clean limit where the mean free path is much larger than the size of vortices.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.