Fluctuations and Phase Transitions in Superconductors

超导体中的涨落和相变

• 批准号: 0302596
• 负责人: Christopher Lobb
• 金额: $ 30万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0302596&HistoricalAwards=false
• 关键词: Fluctuations; Phase; Transitions; Superconductors

This award will support an experimental study of the temperature vs. magnetic field phase diagram of type-II superconductors. The project's goal is to determine if there is a transition in non-zero field, and to determine the critical exponents of that transition if it exists, as well as the exponents of the zero-field transition. (The exponents reported in the literature vary widely for both transitions.) The methods used will be DC I-V and high-frequency (45 MHz to 45 GHz) conductivity measurements on the same samples, providing independent experiments. It is expected that this project will lead to a much-improved understanding of phase transitions in superconductors and in other systems. More broadly, the project will reaffirm that questioning and testing widely-accepted results is an essential part of the scientific process. An important part of this project is the support for training of graduate and undergraduate students. The PIs will continue their strong efforts to involve women and minorities in research, and to collaborate with scientists from Latin America and Eastern Europe. Finally, both PIs will continue their extensive efforts to encourage broader education in science, including work with predominantly minority public-school students. A superconductor, by definition, is a material that has no resistance to the flow of electricity, a property with great potential technological importance. Prior work showed that the consensus concerning the limits of superconductivity, in particular, whether materials are superconducting in a magnetic field, may have been incorrect. This award will support research that will more generally explore under what conditions superconductivity can exist. The project will reaffirm that questioning and testing widely-accepted results is an essential part of the scientific process. An important part of this project is the support for training of graduate and undergraduate students. Both PIs will continue their strong efforts to involve women and minorities in research, and to collaborate with scientists from Latin America and Eastern Europe. Finally, both PIs will continue their extensive efforts to encourage broader education in science, including work with predominantly minority public-school students.

该奖项将支持II型超导体的温度与磁场相图的实验研究。 该项目的目标是确定在非零字段中是否存在过渡，并确定该过渡的关键指数（如果存在）以及零视野过渡的指数。 （文献中报告的指数在两个过渡方面都差异很大。）所使用的方法将是在同一样品上进行的电导率测量，并提供独立的实验。 预计该项目将导致对超导体和其他系统中相变的大量理解。从更广泛的角度来看，该项目将重申质疑和测试广泛认可的结果是科学过程的重要组成部分。 该项目的重要部分是支持培训研究生和本科生。 PI将继续努力使妇女和少数民族参与研究，并与拉丁美洲和东欧的科学家合作。 最后，两个PI将继续他们的广泛努力，以鼓励在科学领域进行更广泛的教育，包括与少数民族公立学校学生的工作。从定义上讲，超导体是一种对电流没有抵抗力的材料，具有巨大的技术重要性。 先前的工作表明，有关超导性限制的共识，特别是在磁场中材料是否在磁场中进行超导，可能是不正确的。 该奖项将支持在哪种条件下可能存在超导性的研究。 该项目将重申质疑和测试广泛认可的结果是科学过程的重要组成部分。 该项目的重要部分是支持培训研究生和本科生。 这两个PI都将继续努力使妇女和少数民族参与研究，并与拉丁美洲和东欧的科学家合作。 最后，两个PI将继续他们的广泛努力，以鼓励在科学领域进行更广泛的教育，包括与少数民族公立学校学生的工作。