项目名称: 基于飞秒电子衍射技术的高温超导BSCCO单晶结构动力学研究
项目编号: No.11304374
项目类型: 青年科学基金项目
立项/批准年度: 2014
项目学科: 数理科学和化学
项目作者: 王兴
作者单位: 中国科学院西安光学精密机械研究所
项目金额: 30万元
中文摘要: 自从1986年铜氧化物高温超导体被发现以来,高温超导体中电子配对的物理机制就一直是凝聚态物理研究领域中的热点和难点。飞秒超快电子衍射技术具有飞秒时间尺度和亚毫埃空间尺度的超高时空分辨率,可实时观察物质内部原子运动的动态过程,是研究强关联电子材料精细结构的有效工具。本课题拟利用飞秒超快电子衍射技术观察高温超导BSCCO 单晶时间分辨的电子衍射图样。通过改变不同实验参量,如样品温度、激光能量和激光偏振方向等得到BSCCO 单晶瞬态变化的电子衍射图样,根据衍射图样中衍射峰、衍射强度等信息研究超导相变过程中的晶格畸变、激光诱导的超导相变以及各向异性的结构动力学,探索高温超导电子-声子耦合的可能机制,为揭示高温超导电性的产生机理提供新的依据和参考。
中文关键词: 飞秒电子衍射;超快电子枪;泵浦探测;自支撑薄膜;
英文摘要: The mechanism of electron pairing of high temperature cuprate superconductors is always the hot topic in condensed matter physics since their discovery in 1986. Ultrafast electron diffraction technique can be used to observe atomic inner movements of materials in real time because it offers both femtosecond temporal resolution and sub-milli-angstrom spatial resolution. In this project, we propose to investigate time-resolved electron diffraction patterns of high temperature superconducting BSCCO single crystal with ultrafast electron diffraction technique. According to the peaks and intensities of the diffraction patterns obtained with various experimental parameters such as temperature of the sample, fluence and polarization of the pump laser, we would study the lattice distortions during the superconducting phase transition, the laser induced phase transition and the anisotropic structural dynamics along the c axis. This study is to provide basis and reference in understanding the glue holding the Cooper pairs in high temperature cuprate superconductors.
英文关键词: Femtosecond electron diffracti;ultrafast electron gun;pump-probe;self-supporting film;