CAREER: A Single Shot Camera Capturing Ultrafast Dynamic Phenomena

本研究的重点是开发超高速成像的新方法。特别是，它将有助于超高速光学和x射线相机的新发展，这些相机能够提供前所未有的空间和时间分辨率的分子电影。这将极大地推动超快光学科学在单分子成像、光-物质相互作用和惯性约束聚变方面的发展。该项目还包括教育活动，如为本科生和研究生开发夏季/冬季光学科学短期课程，以及每年在PI实验室培训一名研究生和两名本科生和/或当地高中生。研究还包括广泛的教育活动，为学生在个人和合作研究设置。传统的泵浦探针方法通常可以提供超快的时间分辨率成像，但它们大多适用于高度可重复的事件。然而，如果事件到事件的重现性是不规则的，或者涉及材料损坏、不可逆化学反应和/或结构相变，则需要进行单次检测。这里的项目是开发一种能够捕捉超快动态图像的单镜头相机，同时记录空间（二维）和时间的演变。这种相机可以以每秒50万亿帧的帧率捕捉图像，单次拍摄可记录3 ~ 60帧。在这里，使能技术包括超宽带频谱生成、超快光脉冲整形和单镜头高光谱成像。这种相机可以潜在地用于材料表征、生物医学成像、生物传感器、光学和等离子体诊断。特别是，它在x射线自由电子激光器中的应用将导致超短电子束成像和表征。

This research is focused on developing new methodologies for ultrafast imaging. In particular, it will contribute to a new development of ultrafast optical and X-ray cameras capable of providing molecular movies with unprecedented spatial and temporal resolution. This will greatly advance ultrafast optical science in single-molecule imaging, light-matter interaction, and inertial confinement fusion. The project also includes educational activities such as developing a summer/winter short course in optical science for undergraduate and graduate students, as well as training one graduate and two undergraduate and/or local high school students per year in the PI's laboratory. The research also includes extensive educational activities for students in individual and collaborative research settings.Conventional pump-probe methods can routinely provide ultrafast time-resolved imaging, but they mostly work for highly repeatable events. However, if event-to-event reproducibility is irregular or involves material damage, irreversible chemical reactions, and/or structural phase transition, single-shot detection is a necessity. The project here is to develop a single-shot camera capable of capturing ultrafast dynamic images, simultaneously recording spatial (2-dimensional) and temporal evolutions in a single-shot. Such a camera can capture images at a frame rate of ~50 trillion frames per second, recording 3 ~ 60 frames in a single-shot. Here, the enabling technologies include ultra-broadband spectrum generation, ultrafast optical pulse shaping, and single-shot hyperspectral imaging. This kind of camera can be potentially used in material characterization, biomedical imaging, bio-sensors, and optical and plasma diagnostics. In particular, its application in X-ray free electron lasers will lead to ultrashort electron beam imaging and characterization.