CAREER: Tuning Topology and Strong Correlations for the Next Generation of Topological Superconductors

该奖项部分由2021年美国救援计划法案（公法117-2）资助。非技术描述：一种理论上预测的量子物质——拓扑超导体——不仅以零电阻导电，而且保护其固有的量子特性不受材料缺陷的影响。通过实验实现这种新材料是实现未来容错量子计算机的关键，这种计算机的性能可以比传统计算机高出几个数量级。然而，这种材料的存在仍然难以捉摸。该项目由材料研究部凝聚态物理项目支持，利用原子级逐层结构制造新一代拓扑超导体，并进行先进的材料表征，以建立这种新物质状态的证据。该项目为实现工业低温温度下的拓扑超导体提供了实质性的一步。它不仅会对凝聚态物理产生深远的影响，而且会对量子科学和工程产生广泛的影响：新的量子计算架构和协议可以建立在这种材料发现的基础上。研究工作与教育和推广主题“沉浸式量子材料教育”相结合，以培训研究生，本科生和高中水平的学生。研究结果通过专门的活动进行传播，例如针对9至11年级学生的“芝加哥大学量子快速入门”研讨会，其中有34%的少数群体来自代表性不足的群体。通过该项目培训的研究生可以在学术界或新兴的量子工程行业中推进他们的职业生涯，形成未来的劳动力，并确保美国在量子科学和量子经济方面的领导地位。技术描述：拓扑超导体是一类新的超导体，有望实现容错量子计算。目前假定的拓扑超导体的材料平台是基于传统超导体和半导体的异质结构，并且需要复杂的工程才能在低于1开尔文的温度下工作。然而，拓扑超导性的结论性测试仍然难以捉摸。本项目的目标有三个方面：1)利用分子束外延对feese /氧化物进行原子级结构调谐以优化其拓扑电子特性；2)利用时间分辨光电发射技术对feese /氧化物进行飞秒动态调谐，揭示拓扑结构与电子-电子相互作用之间的关系；3)利用带阴影掩模的分子束外延制造拓扑量子器件，测试非阿贝尔任意子统计量。该项目通过解决拓扑超导体存在和优化的紧迫问题，可以大大推进拓扑材料领域的发展，并为拓扑超导性与强电子-电子相互作用之间的关系提供变革性的见解。在教育和推广主题“沉浸式量子材料教育”中，首席研究员与各级学生进行拓扑材料的前沿研究。针对本科生的“硕士暑期学校”和针对产业工人的“量子工程与技术证书”等讲习班提高了公众对拓扑超导的认识，使来自代表性不足的少数群体的学生受益。教育方面的努力建立了首席研究员的实验室，作为促进芝加哥南区量子科学和工程通识教育的支柱。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in part under the American Rescue Plan Act of 2021 (Public Law 117-2).NON-TECHNICAL DESCRIPTION: A theoretically predicted quantum matter – a topological superconductor – not only conducts electricity with zero resistance but also protects its innate quantum properties from material imperfections. Experimentally realizing this new material is key to enabling future fault-tolerant quantum computers which can outperform classical computers by orders-of-magnitude. Yet, the existence of such materials remains elusive. This project supported by the Condensed Matter Physics program in the Division of Materials Research utilizes atomic-level layer-by-layer construction to fabricate new generations of topological superconductors, and performs advanced material characterizations to establish the evidence for this new state of matter. This project provides a substantial step forward to realize topological superconductors at temperatures achievable by industrial cryogenics. It can have profound impacts in not only condensed matter physics but also broadly in quantum science and engineering: new quantum computing architectures and protocols can be built on top of this material discovery. The research effort is integrated with an education and outreach theme “Immersive Quantum Material Education” to train students at graduate, undergraduate, and high-school levels. The research results are disseminated through dedicated activities such as the “UChicago Quantum Quickstart” workshop for 9th-to-11th grade students with demonstrated 34% participation from under-represented minority groups. Graduate students trained through this project can advance their careers in academia or in the emerging quantum engineering industry, forming the workforce for the future and ensuring the American leadership in both quantum sciences and quantum economy.TECHNICAL DESCRIPTION: Topological superconductors are a new class of superconductors predicted to enable fault-tolerant quantum computing. Current material platforms for putative topological superconductors are based on heterostructures of conventional superconductors and semiconductors, and require sophisticated engineering only to work at temperatures below 1 Kelvin. Yet, the conclusive test of topological superconductivity remains elusive. The goals of this project are three-fold: 1) performing atomic-level structural tuning of FeTeSe/oxides to optimize the topological electronic properties using molecular beam epitaxy; 2) performing femtosecond dynamical tuning of FeTeSe/oxides to reveal the relationship between topology and electron-electron interactions using time-resolved photoemission; 3) testing non-Abelian anyon statistics by fabricating topological quantum devices using molecular beam epitaxy with shadow masks. This project can substantially advance the field of topological materials by addressing the urgent questions on the existence and optimization of topological superconductors, and provide transformative insights into the relationship between topological superconductivity and strong electron-electron interactions. In the education and outreach theme “Immersive Quantum Material Education,” the principal investigator engages with students at all levels on the cutting-edge research on topological materials. Workshops such as the “MASTER Summer School” for undergraduate students and “Certificate in Quantum Engineering and Technology” for industrial workers promote awareness among the public on topological superconductivity, benefiting students from under-represented minority groups. The educational effort establishes the principal investigator’s laboratory as an anchor to facilitate general education on quantum science and engineering in South Side Chicago.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.