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。

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.