RUI: Fluctuations and Phase Transitions in Iron Pnictide Superconductors

RUI：铁磷族超导体中的涨落和相变

• 批准号: 1305637
• 负责人: Matthew Sullivan
• 金额: $ 18.5万
• 依托单位: Ithaca College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1305637&HistoricalAwards=false
• 关键词: RUI; Fluctuations; Phase; Transitions; Iron

****Technical Abstract****This award supports experimental low-temperature physics research at an undergraduate institution. The scaling analysis of voltage vs. current curves has been an invaluable tool in the study of the normal-superconducting phase transition. However, recent work has shown that the conventional application of this tool is too flexible to uniquely determine the critical parameters, and that extrinsic effects can obscure or destroy the phase transition. With these caveats known, we have successfully applied this technique to study the hole-doped cuprate YBa2Cu3O7 and the electron-doped cuprate Pr2-xCexCuO4. This project will use the same technique to examine the phase transition in the new iron pnictide-122 superconductors (SrFe2As2 and BaFe2As2) both in a magnetic field and in zero magnetic field. This work will lead to an understanding of the model that governs the phase transition in this material and the differences and similarities of the phase transition between iron pnictide superconductors and other superconductors. This project will also train undergraduate students in experimental and low-temperature physics in preparation for graduate work or industry careers. In addition, to encourage broader education in science, this project will contribute to an existing outreach program with local public schools and submit video demonstrations to YouTube.****Non-Technical Abstract****This award supports experimental low-temperature physics research at an undergraduate institution. "High-Temperature" superconductors, discovered more than a quarter of a century ago, still hold great promise and great challenges. The promise lies in the hope of eventually making superconductors with much higher transition temperatures, and the challenges lie in the fact that we do not, even 25 years later, fully understand how or why these materials superconduct. Superconductors made from iron and arsenic, discovered in 2008, are the latest in an array of unusual materials to display superconductivity. This individual investigator award supports a project that will study how iron- and arsenic-based materials become superconducting, comparing them to copper-oxygen based superconductors and conventional, single element superconductors, all in the hopes of understanding the underlying mechanism that creates superconductivity in these materials. The proposed studies will add to the knowledge of high-temperature superconductors and help fulfill the promise of attaining higher transition temperatures. This project will also train undergraduate students in state-of-the-art sample growth, characterization, and measurement techniques. This project will also contribute to broader educational goals by fostering science outreach to local schools and promoting the research via online video demonstrations.

****技术摘要****该奖项支持本科机构的实验低温物理研究。电压与电流曲线的标度分析一直是正常超导相变研究中的宝贵工具。然而，最近的工作表明，该工具的常规应用过于灵活，无法唯一确定关键参数，并且外在效应可能会掩盖或破坏相变。知道这些注意事项后，我们已成功应用该技术来研究空穴掺杂铜酸盐 YBa2Cu3O7 和电子掺杂铜酸盐 Pr2-xCexCuO4。该项目将使用相同的技术来检查新型铁磷化物 122 超导体（SrFe2As2 和 BaFe2As2）在磁场和零磁场中的相变。这项工作将有助于理解控制这种材料相变的模型，以及铁磷族超导体和其他超导体之间相变的异同。该项目还将对本科生进行实验和低温物理方面的培训，为研究生工作或行业职业生涯做好准备。此外，为了鼓励更广泛的科学教育，该项目将为当地公立学校现有的推广计划做出贡献，并向 YouTube 提交视频演示。****非技术摘要****该奖项支持实验低温物理在本科机构进行研究。四分之一个多世纪前发现的“高温”超导体仍然具有巨大的前景和巨大的挑战。前景在于最终制造出具有更高转变温度的超导体，而挑战在于，即使在 25 年后，我们仍然没有完全理解这些材料如何或为何超导。 2008 年发现的由铁和砷制成的超导体是一系列表现出超导性的不寻常材料中最新的一种。该个人研究员奖支持一个项目，该项目将研究铁基和砷基材料如何变得超导，并将它们与铜氧基超导体和传统的单元素超导体进行比较，所有这些都希望了解在这些材料中产生超导性的根本机制。材料。拟议的研究将增加高温超导体的知识，并有助于实现获得更高转变温度的承诺。该项目还将对本科生进行最先进的样品生长、表征和测量技术方面的培训。该项目还将通过促进当地学校的科学推广并通过在线视频演示促进研究，为更广泛的教育目标做出贡献。