EAGER: Resolving the issue of pairing symmetry in Sr2RuO4

EAGER：解决 Sr2RuO4 中的配对对称性问题

• 批准号: 2312899
• 负责人: Ying Liu
• 金额: $ 25.32万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2312899&HistoricalAwards=false
• 关键词: EAGER; Resolving; issue; pairing; symmetry

Non-technical description:Superconductivity is a macroscopic quantum phenomenon highly relevant to quantum computing and other quantum technologies. The drive towards quantum computing calls for deeper understanding of the fundamental physics of superconductivity. For example, the implementation of fault tolerant topological quantum computing may be achievable with exotic spin-triplet superconductors. Single-layer strontium ruthenate (SRO) had been a leading candidate for a spin-triplet superconductor up to 2019. However, it turned out that one of the experiments that supported that claim in SRO is incorrect. This led to a controversy on the nature of superconductivity in this material. This experimental and theoretical project will aim to address this controversy as well as train future scientists from underrepresented minority communities in STEM to help meet the human resource needs of emerging quantum technologies.Technical description:The symmetry properties of the superconducting order parameter, which consists of orbital and spin parts, are of fundamental interest for superconductivity research. Single-layer strontium ruthenate (SRO) was considered a leading candidate for spin-triplet superconductivity up to 2019 when results from an important NMR Knight shift experiment from 1998, which probes the spin part of the order parameter, was shown to be incorrect. This led to suggestions by some researchers that SRO is actually a spin singlet. On the other hand, the Josephson effect based phase-sensitive experiments on SRO, which have remained largely unchallenged, suggest that the orbital part of the order parameter in SRO is of an odd parity, which implies that SRO is a spin triplet due to the presence of an inversion symmetry in this material. The heated debate on the pairing symmetry in SRO calls for new theoretical insights and additional experimental inputs. This project aims to strengthen the previous determination of the odd parity order parameter in SRO as well as identify ways to reconcile this with work probing the spin degrees of freedom.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.

非技术描述：超导性是一种与量子计算和其他量子技术高度相关的宏观量子现象。迈向量子计算的动力需要更深入地了解超导性的基本物理。例如，外在的自旋三个超导体可以实现容错拓扑量子计算的实现。直到2019年，单层畸形酸盐（SRO）一直是旋转三角体超导体的领先候选者。但是，事实证明，其中一个支持SRO主张的实验是不正确的。这导致了有关该材料超导性的性质的争议。这个实验和理论项目将旨在解决这一争议，并培训STEM中代表性不足的少数民族社区的未来科学家，以帮助满足新兴量子技术的人力资源需求。技术描述：超导订单参数的对称性属性，具有轨道和旋转零件的超级零件，对超级领域的兴趣具有基本利益。直到2019年，单层畸形酸盐（SRO）被认为是自旋三链超导性超导性的领先候选者，当时从1998年起，重要的NMR骑士偏移实验的结果显示，该实验探测了顺序参数的旋转部分，显示出不正确的。这导致一些研究人员的建议，SRO实际上是一个旋转的单线。另一方面，基于Josephson效应对SRO的相位敏感实验，该实验在很大程度上没有受到挑战，这表明SRO中的顺序参数的轨道部分是奇怪的，这意味着SRO是由于这种材料中的反式对称性的存在，因此SRO是一个自旋三重态。 SRO中关于配对对称性的激烈争论要求提供新的理论见解和其他实验输入。该项目旨在加强SRO中奇数式订单参数的先前确定，并确定与探索自由度的工作调和的方法。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来获得支持的。