CAREER: Non-equilibrium Dynamics in Cuprate Superconductors Studied by Coherent Ultrafast Spectroscopy and Ultrafast Electron Diffraction

职业：通过相干超快光谱和超快电子衍射研究铜酸盐超导体的非平衡动力学

• 批准号: 0845296
• 负责人: Nuh Gedik
• 金额: $ 55万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0845296&HistoricalAwards=false
• 关键词: CAREER; Non; equilibrium; Dynamics; Cuprate

Non-Technical abstract:This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This CAREER award funds a project to understand the mechanism of superconductivity in cuprates by studying dynamics of ultrafast events taking place at the atomic scale. Superconductivity is the total loss of electrical resistance below a critical temperature. Currently, copper oxygen based cuprate superconductors have the highest known transition temperatures. Even in these materials, the transition temperatures are far below the room temperature which hinders potential applications and the mechanism of superconductivity is still not known. This project will use ultrashort laser pulses to make atomic scale ?movies? of dynamics of electrons and the lattice structure with both spatial and temporal resolutions. Information obtained from these measurements will help to understand the complex interactions leading to high temperature superconductivity in cuprates which may in turn enable predicting superconductors with higher transition temperatures. A strong emphasis will be placed on developing education and outreach programs integrated to the research component of this project. The education component of this project will enable training of graduate and undergraduate students capable of applying these techniques to different fields. A graduate level course dedicated to the application of ultrafast techniques to condensed matter physics will be developed and its material will be made freely available through the internet. The outreach part of this program will contribute improving the quality of K-12 math and science education especially in socio-economically impacted regions. This will be achieved by working closely with math and science oriented charter schools and education research institutions. Technical abstract:This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The goal of this Early Faculty CAREER project is to understand the mechanism of superconductivity in cuprates by studying the dynamics of their low energy excitations and phase transitions. After photoexcitation by ultrashort light pulses, the recovery of the resulting non-equilibrium state will be probed in both space and time using either light or electron pulses providing information about evolution of electronic and structural degrees of freedoms. In the high excitation density limit, non-equilibrium phase transitions will be induced into states that can be either thermally accessible or completely novel. Studying the dynamics of these phase changes will provide crucial information about the competing states of these materials and yield clues about their complex phase diagram. By studying the weak excitation limit, important insights will be obtained into the nature of couplings between different internal degrees of freedoms. A strong emphasis will be placed on developing education and outreach programs integrated to the research component of this project. The education component of this project will enable training of graduate and undergraduate students capable of applying these techniques to different fields. A graduate level course dedicated to the application of ultrafast techniques to condensed matter physics will be developed and its material will be made freely available through the internet. The outreach part of this program will contribute improving the quality of K-12 math and science education especially in socio-economically impacted regions. This will be achieved by working closely with math and science oriented charter schools and education research institutions.

非技术摘要：该奖项是根据2009年《美国复苏与再投资法》（公法111-5）资助的。该职业奖为一个项目提供了一项项目，以了解库酸酯中超导性的机制，通过研究以原子量表进行的超快事件的动态。超导性是低于临界温度以下的电阻的总损失。目前，铜氧基库酸酯超导体具有最高的已知过渡温度。即使在这些材料中，过渡温度也远低于阻碍潜在应用的室温和超导性的机理。该项目将使用超短激光脉冲制作原子量表？电影？具有空间和时间分辨率的电子和晶格结构的动力学。从这些测量值获得的信息将有助于理解导致铜酸盐高温超导性的复杂相互作用，这反过来又可以预测具有较高过渡温度的超导体。将非常重视与该项目的研究部分集成的教育和外展计划。该项目的教育部分将使能够将这些技术应用于不同领域的研究生和本科生培训。将开发用于将超快技术应用于凝结物理物理学的研究生级课程，并将通过互联网免费提供其材料。该计划的推广部分将有助于提高K-12数学和科学教育的质量，尤其是在社会经济影响地区。这将通过与数学和科学的特许学校和教育研究机构紧密合作来实现。 技术摘要：该奖项是根据2009年《美国复苏与再投资法》（公法111-5）资助的。这个早期教师职业项目的目的是通过研究其低能量激励和相变的动态来了解铜酸盐中超导性的机制。在超时光脉冲引起光激发后，将使用光或电子脉冲在空间和时间上探测所得的非平衡状态的恢复，从而提供有关自由的电子和结构性程度的信息。在高激发密度极限中，非平衡相变将被诱导到可以易于访问或完全新颖的状态中。研究这些阶段变化的动力学将提供有关这些材料的竞争状态的重要信息，并产生有关其复杂相图的线索。通过研究弱激发极限，将在不同内部自由度之间的耦合性质中获得重要的见解。将非常重视与该项目的研究部分集成的教育和外展计划。该项目的教育部分将使能够将这些技术应用于不同领域的研究生和本科生培训。将开发用于将超快技术应用于凝结物理物理学的研究生级课程，并将通过互联网免费提供其材料。该计划的推广部分将有助于提高K-12数学和科学教育的质量，尤其是在社会经济影响地区。这将通过与数学和科学的特许学校和教育研究机构紧密合作来实现。