Manipulating 2D Superconductivity through atomic scale control of boundary conditions

通过边界条件的原子尺度控制来操纵二维超导

• 批准号: 1506678
• 负责人: Chih-Kang Shih
• 金额: $ 38.28万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1506678&HistoricalAwards=false
• 关键词: Manipulating; 2D; Superconductivity; through; atomic

NON-TECHNICAL ABSTRACT:This proposal is aimed at controlling the properties of thin superconductor films in the range of only a few atomic monolayers and studying the superconducting properties in this new regime. The superconducting films in such a thin regime are likely to exhibit properties that are not found in the bulk form. For example, such a thin film may be able to carry supercurrent in the presence of very high magnetic fields making the film much more useful for device applications. The research activities involve state-of-the-art synthesis techniques that can lay down the thin film atomic layer by atomic layer thus enabling us to achieve the ultimate material control at the microscopic scale. In addition, we will use characterization tools to study the superconducting properties from nanometer to macroscopic (millimeter) length scales. The proposal focuses on the integration of research and education to train internationally competitive students in materials research. We are also committed to educational outreach to broader audiences at all levels. At UT-Austin the PI will take advantage of the Summer Academy of Nanoscience and Nanotechnology for state-wide high school teachers and students, previously established under the IGERT program. Moreover, we will offer summer internship opportunities for female high school students through the Alice in the Wonderland program; the PI has already hosted four of these students as summer interns and will continue to do so in future years. Finally, this program is fully committed to broadening participation of under-represented groups in graduate research with specific goals of increasing the percentage of graduate students that are women or/and of Hispanic background. TECHNICAL ABSTRACT:Elegantly fabricated functional materials with reduced dimensions occupy a central stage of modern materials research. Supported by an NSF-FRG program in the past, the PI has been focusing on the novel physical properties of precisely tailored metallic thin films and related nanostructures in the quantum regime. These past efforts have substantially advanced the field in terms of growth and characterization of such structures. In the proposed program, we will take another leap forward by creating new heterostructures based on these quantum films to explore and harness their emergent exotic superconducting properties for potential applications. Specifically, we will focus on the interplay of superconductivity with three different quantum degrees of freedom, including electronic, lattice, and spin, and we will implement the following four major task areas: (a) Correlating microscopic and macroscopic measurements - manipulating structural defects and investigating their roles on phase fluctuations; (b) Revisiting quantum size effect on superconductivity ultra-thin films and unraveling the quantum confinement of phonons; (c) Tuning superconductivity of atomic-layer superconducting films with interfacial engineering; and (d) Exploring superconducting - spin-paramagnetic (SC-SP) transition in ultra-thin epitaxial films.

非技术摘要：该提案旨在控制仅几个原子单层范围内的薄超导膜的性质，并研究该新制度中的超导体特性。 如此薄的薄膜中的超导膜很可能表现出以散装形式发现的特性。 例如，这种薄膜在存在很高磁场的情况下可能能够携带超电流，从而使膜对设备应用更有用。 研究活动涉及最先进的合成技术，可以通过原子层铺设薄膜原子层，从而使我们能够在微观范围内实现最终的材料控制。 此外，我们将使用表征工具来研究从纳米到宏观（毫米）长度尺度的超导特性。 该提案着重于将研究和教育的整合到培训国际竞争力的材料研究中的培训。 我们还致力于对各个级别的广泛观众进行教育宣传。 在UT-Austin，PI将利用纳米科学和纳米技术学院的优势，为州范围的高中教师和学生提供以前在IGERT计划下建立的。 此外，我们将通过爱丽丝仙境计划为女性高中生提供暑期实习机会； PI已经接待了其中四个学生作为暑期实习生，并将在未来几年继续这样做。 最后，该计划完全致力于扩大代表性不足的小组在研究生研究中的参与，其特定目标是增加女性或/和/和西班牙裔背景的研究生百分比。技术摘要：尺寸降低的优雅制造的功能材料占据了现代材料研究的中心阶段。在过去的NSF-FRG程序的支持下，PI一直集中在量子状态下精确量身定制的金属薄膜和相关纳米结构的新型物理特性。这些过去的努力在这种结构的增长和表征方面已经大大推动了领域。在拟议的计划中，我们将通过基于这些量子膜创建新的异质结构来探索和利用其新兴的异国情调的超导性特性，以实现潜在应用。 具体而言，我们将重点关注超导性与三个不同的量子自由度的相互作用，包括电子，晶格和自旋，我们将实施以下四个主要任务领域：（a）将显微镜和宏观测量值 - 操纵结构性缺陷并研究其在相位波动上的序列； （b）重新审视量子大小对超导性超薄膜的影响，并阐明声子的量子限制； （c）通过界面工程调节原子层超导膜的超导性； （d）探索超导薄膜中的超导 - 自旋 - parmagnetic（SC-SP）过渡。