Manipulating Majorana bound states in S-TI-S Josephson junction networks: braiding, fusion, and parity dynamics

操纵 S-TI-S 约瑟夫森结网络中的马约拉纳束缚态：编织、融合和宇称动力学

• 批准号: 2004825
• 负责人: Dale Van Harlingen
• 金额: $ 76万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004825&HistoricalAwards=false
• 关键词: Manipulating; Majorana; bound; states; TI

Non-Technical Abstract:This award combines experimental condensed matter physics and quantum information science research aimed at understanding a newly-discovered class of materials and developing schemes for incorporating them into advanced electronic devices for quantum computing. The focus is on topological materials whose properties depend on the topology, or geometry, of their electronic structure, enabling novel electronic states that can carry and control currents in unique ways. Fabricating and measuring a series of advanced hybrid devices that integrate these topological materials with superconductors will enable exploration of the capabilities and limitations of this approach that has been predicted to exhibit new physical phenomena and electronic properties. In addition to their scientific interest, these unique materials can be implemented in electronic circuits to create a new type of computer platform in which the information is stored in quantum states protected from the detrimental effects of the environment, a unique feature of topological devices that has the potential to extend dramatically the speed and capability of large-scale computers. Through the new science and applications that may arise from this project, this research program exposes a diverse cadre of postdoctoral researchers, graduate research students, and undergraduate students to scientific issues and experimental techniques relevant to the development and applications of new materials and phenomena. This training at the interface of materials science and device physics has been demonstrated to be highly effective in launching the careers of scientists and engineers in high technology fields.Technical Abstract: Exciting new phenomena have been predicted to arise in hybrid superconductor-topological insulator systems in which pair correlations induce an effective complex superconducting order parameter exhibiting chiral edge states, topologically-protected surface states, and Majorana fermions, exotic excitations that are their own antiparticles. This project focuses on schemes to nucleate these exotic excitations and manipulate them in controllable ways to verify their existence and explore their stability and dynamics. A series of specific experiments are designed to reveal their unique non-Abelian statistics and to develop functional approaches to image, manipulate, readout the parity that encodes their critical phase information, and braid them to perform logical operations, all critical steps toward understanding the underlying physics of these novel states and crafting a technology for quantum information processing, quantum metrology, and quantum simulation/computing. Key experiments fall into two categories: (1) investigation and characterization of the parity dynamics of Majorana states in S-TI-S Josephson junctions and determine the materials and device properties that affect it --- this includes experiments to observe and characterize parity fluctuations, modeling of the interplay of Josephson phase dynamics and parity transitions, and ways to improve parity lifetimes, (2) development of schemes for braiding, fusion, and parity readout of Majorana modes in the S-TI-S platform, all important capabilities required to implement scheme. The field of topological physics is very new and researchers worldwide are collectively just starting to explore the materials, measurements, and theoretical concepts that will be important in achieving an understanding of Majorana fermions and how to exploit them in electronic circuits. This project explores the key unsolved problems in this field and paths for making significant advances in understanding the nature of exotic Majorana fermions and implementing them in functional superconductor circuits. It also provides opportunities to train students in the science and technology of this field that is anticipated to grow in the coming years.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.

非技术摘要：该奖项结合了实验凝聚态物理和量子信息科学研究，旨在了解新发现的一类材料并开发将其纳入先进电子设备以进行量子计算的方案。 重点是拓扑材料，其特性取决于其电子结构的拓扑或几何形状，从而实现能够以独特方式承载和控制电流的新型电子态。 制造和测量一系列将这些拓扑材料与超导体集成的先进混合设备将能够探索这种方法的能力和局限性，预计这种方法将表现出新的物理现象和电子特性。 除了它们的科学兴趣之外，这些独特的材料还可以在电子电路中实现，以创建一种新型的计算机平台，其中信息存储在量子态中，免受环境的有害影响，这是拓扑器件的独特功能，有可能大幅扩展大型计算机的速度和能力。 通过该项目可能产生的新科学和应用，该研究项目让博士后研究人员、研究生和本科生等多元化干部接触到与新材料和新现象的开发和应用相关的科学问题和实验技术。 这种材料科学和器件物理界面的培训已被证明对于开启高科技领域科学家和工程师的职业生涯非常有效。技术摘要：预计混合超导-拓扑绝缘体系统中会出现令人兴奋的新现象，其中配对相关性诱导出有效的复杂超导有序参数，该参数表现出手性边缘态、拓扑保护表面态和马约拉纳费米子、奇异态 激发是它们自己的反粒子。 该项目重点关注使这些奇异激发成核并以可控方式操纵它们的方案，以验证它们的存在并探索它们的稳定性和动力学。 一系列具体的实验旨在揭示它们独特的非阿贝尔统计数据，并开发功能方法来成像、操纵、读出编码其关键相位信息的奇偶校验，并将它们编织起来执行逻辑运算，所有这些关键步骤都是为了理解这些新状态的底层物理原理，并为量子信息处理、量子计量和量子模拟/计算打造技术。 关键实验分为两类：（1）研究和表征S-TI-S约瑟夫森结中马约拉纳态的宇称动力学，并确定影响它的材料和器件特性——这包括观察和表征宇称波动的实验、约瑟夫森相动力学和宇称跃迁相互作用的建模以及提高宇称寿命的方法，（2）开发编织方案， S-TI-S 平台中马约拉纳模式的融合和奇偶校验读出，是实施方案所需的所有重要功能。 拓扑物理领域是一个非常新的领域，世界各地的研究人员才刚刚开始探索材料、测量和理论概念，这些对于理解马约拉纳费米子以及如何在电子电路中利用它们非常重要。 该项目探讨了该领域尚未解决的关键问题，以及在理解奇异马约拉纳费米子的性质并将其应用于功能超导电路方面取得重大进展的途径。 它还提供了在该领域的科学和技术方面培训学生的机会，该领域预计将在未来几年发展。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Decoherent quench dynamics across quantum phase transitions

• DOI: 10.21468/scipostphys.11.4.084
• 发表时间: 2021-03
• 期刊: SciPost Physics
• 影响因子: 5.5
• 作者: W. Kuo;D. Arovas;S. Vishveshwara;Yi-Zhuang You

Signatures of Majorana bound states and parity effects in two-dimensional chiral p -wave Josephson junctions

• DOI: 10.1103/physrevb.105.214521
• 发表时间: 2022-02
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Nick Abboud;V. Subramanyan;Xiao-Qi Sun;G. Yue;D. V. Van Harlingen;S. Vishveshwara