Lee Young Min, Kim Young Jae, Kim Ye-Jin, Kwon Oh-Hoon
Department of Chemistry, School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, South Korea.
Struct Dyn. 2017 May 8;4(4):044023. doi: 10.1063/1.4983226. eCollection 2017 Jul.
In the past decade, we have witnessed the rapid growth of the field of ultrafast electron microscopy (UEM), which provides intuitive means to watch atomic and molecular motions of matter. Yet, because of the limited current of the pulsed electron beam resulting from space-charge effects, observations have been mainly made to periodic motions of the crystalline structure of hundreds of nanometers or higher by stroboscopic imaging at high repetition rates. Here, we develop an advanced UEM with robust capabilities for circumventing the present limitations by integrating a direct electron detection camera for the first time which allows for imaging at low repetition rates. This approach is expected to promote UEM to a more powerful platform to visualize molecular and collective motions and dissect fundamental physical, chemical, and materials phenomena in space and time.
在过去十年中，我们见证了超快电子显微镜（UEM）领域的迅速发展，它为观察物质的原子和分子运动提供了直观手段。然而，由于空间电荷效应导致脉冲电子束的电流有限，目前主要通过高重复率的频闪成像对数百纳米及以上的晶体结构的周期性运动进行观测。在此，我们首次集成了直接电子检测相机，开发出一种具有强大功能的先进UEM，能够克服当前的局限性，实现低重复率成像。这种方法有望将UEM提升为一个更强大的平台，用于可视化分子和集体运动，并在时空上剖析基本的物理、化学和材料现象。
