EAGER: SUPER: Coupling High-Energy Phonons into High-Tc Superconductors

EAGER：SUPER：将高能声子耦合到高温超导体中

• 批准号: 2132343
• 负责人: Yu He
• 金额: $ 30万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2132343&HistoricalAwards=false
• 关键词: EAGER; SUPER; Coupling; Energy; Phonons

NONTECHNICAL SUMMARYThis EAGER project supports research and education activities to create a more robust superconductor with the help from light elements on the periodic table. Superconductivity - the lossless transmission of electricity in a solid-state material - most commonly relies on the formation of electron pairs due to an attraction provided by atomic vibrations. In most bulk superconductors, this vibration is too slow to maintain the electron pairing at everyday temperatures - lots of electrons with little glue. Compounds with light elements naturally contain the fastest atomic vibrations, but the highly vibrative nature also prevents the formation of a stable, compact crystal lattice that can conduct electricity - a lot of glue with few electrons.The main goal of this EAGER project is to use advanced synthesis to create a stable and compact crystal lattice enriched with light elements such as hydrogen, carbon and lithium. This would provide both sufficient electrons and pairing glue simultaneously, therefore strengthening superconductivity to weather ambient conditions. One way is to create preferred light-element occupation sites in existing layered bulk superconductors via selected large molecule intercalation. The other is to grow high-temperature superconductors on light-element substrates layer-by-layer. Both methods are aimed to create atomic confinement of light elements in proximity to pre-existing superconducting electrons.This project supports the education of three graduate students, cohesively working across the full cycle of synthesis, characterization and theory. The intuitive and generic conceptual approach is to be developed as an important teaching example in upper division college physics curriculum. This project also offers a demonstration of the modern materials design pipeline, which will be used to develop research projects of undergraduate and public-school students.TECHNICAL SUMMARYThis EAGER project supports research and education activities that investigate the possible use of high-frequency phonons from light elements to boost superconductivity in existing high-temperature superconductors. In particular, lithium and hydrogen rich compounds will be used to boost the transition temperature and critical supercurrent of copper- and iron-based superconductors. Unlike traditional methods, which often result in uncontrolled light element placement and structural damage to the treated material, this project aims to better regulate the process with i) a dopant-assisted light-element intercalation in bulk materials, and ii) light element substrate-enhanced superconductivity in thin film superconductors. The first method creates preferred light-element occupation sites in existing layered bulk superconductors via selected large molecule intercalation. The other method aims to grow high-temperature superconductors on light-element substrates layer-by-layer. In practice, via both approaches, a highly ordered solid state structure with enriched light element composition is to be created and stabilized under ambient conditions. This project examines the effectiveness of the general framework of “hybrid” superconductivity, achieved via targeted combination of favorable superconducting contributors - strong pairing and strong conduction. The proposed bulk and thin-film synthesis complement each other in terms of tunability and applicable characterization methods. This project supports the education of three graduate students, cohesively working across the full cycle of synthesis, characterization and theory. The intuitive and generic conceptual approach is to be developed as an important teaching example in upper division college physics curriculum. This project also offers a demonstration of the modern materials design pipeline, which will be used to develop research projects of undergraduate and public-school students.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.

非技术摘要这个 EAGER 项目支持研究和教育活动，以借助元素周期表中的轻元素创建更坚固的超导体。超导性（固态材料中的无损电力传输）通常依赖于电子对的形成。在大多数块状超导体中，这种振动太慢而无法在日常温度下维持电子配对 - 轻元素化合物中自然含有大量电子。原子振动，但高振动性质也阻止了以最快的速度形成稳定、致密的导电晶格——大量胶水和少量电子。这个 EAGER 项目的主要目标是使用先进的合成方法来创建稳定的富含氢、碳和锂等轻元素的致密晶格，这将同时提供足够的电子和配对胶，因此增强超导性以适应环境条件。一种方法是创造优选的轻元素占据。另一种方法是通过选定的大分子嵌入在现有的层状体超导体中生长高温超导体，这两种方法都旨在将轻元素限制在现有超导附近。该项目支持三名研究生的教育，在综合、表征和理论的整个周期中紧密合作，将开发直观和通用的概念方法作为重要的教学实例。高年级大学物理课程。该项目还提供了现代材料设计流程的演示，该流程将用于开发本科生和公立学校学生的研究项目。技术摘要该 EAGER 项目支持研究和教育活动，调查可能的用途来自轻元素的高频声子可提高现有高温超导体的超导性，特别是富含锂和氢的化合物将用于提高铜基和铁基的转变温度和临界超电流。与传统方法不同，传统方法通常会导致轻元素放置不受控制并对处理的材料造成结构损坏，该项目旨在通过i）散装材料中的掺杂剂辅助轻元素嵌入和ii）轻元素来更好地调节该过程。第一种方法是通过选定的大分子嵌入在现有的层状块体超导体中创建优选的轻元素占据位点。在实践中，通过这两种方法，将在环境条件下创建并稳定具有丰富轻元素成分的高度有序的固态结构。 “混合”超导，通过有针对性的组合有利的超导贡献者——强配对和强传导来实现。所提出的体和薄膜合成在可调谐性和适用的表征方法方面相互补充。三位研究生在合成、表征和理论的整个周期中紧密合作，将开发直观和通用的概念方法作为高年级大学物理课程的重要教学实例。该奖项将用于开发本科生和公立学校学生的研究项目。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

High-temperature superconductivity survives

高温超导依然存在

• DOI: 10.1038/s41563-023-01552-x
• 发表时间: 2023-06
• 期刊: Nature Materials
• 影响因子: 41.2
• 作者: He; Yu
• 通讯作者: Yu

Absence of a BCS-BEC crossover in the cuprate superconductors

铜酸盐超导体中不存在 BCS-BEC 交叉

• DOI: 10.1038/s41535-023-00550-1
• 发表时间: 2022-10-24
• 期刊: npj Quantum Materials
• 影响因子: 5.7
• 作者: J. Sous;Yu He;S. Kivelson
• 通讯作者: S. Kivelson

Role of electron-phonon coupling in excitonic insulator candidate Ta2NiSe5

电子-声子耦合在激子绝缘体候选 Ta2NiSe5 中的作用

• DOI: 10.1103/physrevresearch.5.043089
• 发表时间: 2023-10
• 期刊: Physical Review Research
• 影响因子: 4.2
• 作者: Chen, Cheng;Chen, Xiang;Tang, Weichen;Li, Zhenglu;Wang, Siqi;Ding, Shuhan;Kang, Zhibo;Jozwiak, Chris;Bostwick, Aaron;Rotenberg, Eli;et al
• 通讯作者: et al