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: 1341286
• 负责人: Eric Hudson
• 金额: $ 37.63万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-28 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1341286&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）中电子态的性质和行为是许多争论的中心。 在超导转变温度以上观察到的赝能隙态被一些人视为超导态的前兆。 其他人则将其视为一个竞争阶段。尽管进行了大量的实验和理论工作，这个问题仍然备受争议，并且是我们对高温超导总体理解的核心。该个人研究者奖支持通过温度依赖性扫描隧道显微镜 (STM) 对这种关系的研究。实验将在 Bi2Sr2CuO6+x 和 YBa2Cu3O6+x 中进行，其中我们之前已经观察到竞争相的证据，而 YBa2Cu3O6+x 则更常被研究，但尚未使用最近开发的 STM 技术进行研究。超高真空、变温扫描隧道显微镜是一项要求很高的实验技术；高温超导作为强相关电子系统的一部分，处于凝聚态物理的中心。因此，该项目将成为学生的绝佳训练场。此外，该奖项将支持在高温超导令人信服的科学奥秘和技术前景的推动下，向广大受众推广科学。****非技术摘要****超导体是可以承载电流而没有电阻和由此产生的能量损失的材料通过热量产生。不幸的是，这种技术上有用的特性仅在非常低的温度下（低于“转变温度”）才会发挥作用。就在二十多年前，人们发现了一类新的“高温超导体”，其转变温度接近 100 K。与室温 (300 K) 相比，这仍然非常冷，但它带来了密集的技术，例如能源基础设施、和科学发展。该个人研究员奖支持高温超导体的实验研究，目的是了解其高于转变温度（甚至在某些材料中高于室温）的非常规特性与超导性之间的关系。有人提出，这些较高温度的特性与超导性竞争或干扰，并且通过理解和控制它们，转变温度可能会显着提高。在研究该提案的同时，学生将接受广泛的实验技术培训。此外，高温超导令人信服的科学奥秘和技术前景使科学能够向广大受众推广，这也得到了该奖项的支持。