Disentangling Pseudogap from Superconductivity in the Cuprates by Scanning Tunneling Microscopy

通过扫描隧道显微镜解开铜酸盐中的赝能隙与超导性

• 批准号: 0904400
• 负责人: Eric Hudson
• 金额: $ 46.14万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0904400&HistoricalAwards=false
• 关键词: Disentangling; Pseudogap; Superconductivity; Cuprates; Scanning

****TECHNICAL ABSTRACT****The nature and behavior of electronic states in high temperature superconductors (HTS) are the center of much debate. The pseudogap state, observed above the superconducting transition temperature, is seen by some as a precursor to the superconducting state. Others view it as a competing phase. Despite much experimental and theoretical work, this question remains highly debated and central to our understanding of HTS in general. This individual investigator award supports the investigation of this relationship by temperature dependent scanning tunneling microscopy (STM). Experiments will be performed in both Bi2Sr2CuO6+x, in which we have previously observed evidence for a competing phase, and YBa2Cu3O6+x, which is more commonly studied but has not been investigated with recently developed STM techniques. Ultrahigh vacuum, variable temperature scanning tunneling microscopy is a demanding experimental technique; HTS, as part of the broad class of strongly correlated electron systems, are at the center of much condensed matter physics. Hence this project will be an excellent training ground for students. Furthermore, this award will support science outreach to broad audiences driven by the compelling scientific mystery and technological promise of high temperature superconductivity.****NON-TECHNICAL ABSTRACT****Superconductors are materials that can carry current without resistance and resultant energy losses through heat generation. Unfortunately, this technologically useful property only turns on at very low temperatures, below a "transition temperature." Just over twenty years ago a new class of "High Temperature Superconductors" were discovered, with transition temperatures near 100 K. This is still very cold compared to room temperature (300 K), but has led to intense technological, such as energy infrastructure, and scientific development. This individual investigator award supports the experimental investigation of high temperature superconductors with the goal of understanding the relationship between their unconventional properties above the transition temperature (even above room temperature in some materials) and superconductivity. It has been proposed that these higher temperature properties compete, or interfere, with superconductivity, and that by understanding and controlling them transition temperatures may be significantly increased. While investigating this proposal, students will be trained in a wide range of experimental techniques. Furthermore, the compelling scientific mystery and technological promise of high temperature superconductivity enables scientific outreach to broad audiences, also supported by this award.

****技术摘要****高温超导体（HTS）中电子状态的性质和行为是许多争论的中心。 假立状态在超导过渡温度上方观察到的伪态状态被某些人视为超导状态的前体。 其他人则将其视为竞争阶段。尽管实验性和理论工作很多，但这个问题仍然是我们对HTS的理解的质疑，并且至关重要。该单独的研究者奖通过温度依赖的扫描隧道显微镜（STM）支持对这种关系的研究。实验将在BI2SR2CUO6+X中进行，我们以前已经观察到了竞争阶段的证据，而YBA2CU3O6+X进行了更常见的研究，但尚未通过最近开发的STM技术进行了研究。超高真空，可变的温度扫描隧道显微镜是一种苛刻的实验技术。作为广泛相关的电子系统的一部分，HTS是许多冷凝物质物理学的中心。因此，这个项目将是学生的绝佳培训场所。此外，该奖项将支持科学宣传对高温超导性的令人信服的科学神秘和技术希望所驱动的广泛观众的宣传。不幸的是，该技术上有用的特性仅在非常低的温度下打开，低于“过渡温度”。二十多年前，发现了一类新的“高温超导体”，其过渡温度接近100K。与室温相比，这仍然非常冷，但导致了强烈的技术，例如能源基础设施和科学发展。该个体研究者奖支持对高温超导体的实验研究，目的是了解其在过渡温度以上（甚至在某些材料中甚至高于室温）的非常规性能之间的关系和超导性。已经提出，这些较高的温度特性会与超导性竞争或干扰，并且通过理解和控制它们的过渡温度可能会显着升高。在调查此建议时，将对学生进行各种实验技术的培训。此外，高温超导性的引人入胜的科学神秘和技术希望使该奖项的科学宣传能够对广泛的受众进行。