Femtosecond transmission electron microscopy for nanoscale photonics: a numerical study.
Femtosecond transmission electron microscopy for nanoscale photonics: a numerical study.
复制标题
DOI：
10.1039/c8nr06235h
复制
发表时间：
2018-11
期刊：
影响因子：
6.7
通讯作者：
C. W. Barlow Myers;N. J. Pine;W. Bryan
中科院分区：
文献类型：
--
作者：
C. W. Barlow Myers;N. J. Pine;W. Bryan
超快电子显微镜的最新发展表明，可以在非常小和快速的尺度上同时收集空间和时间信息。在目前的工作中，仪器设计研究与应用纳米级动力学，我们优化了飞秒透射电子显微镜（fs-TEM）的条件。的fs-TEM数值研究采用了金属nanotip源，静电加速，磁透镜，样品周围的冷凝器，目标和时间压缩机，并考虑在传播过程中的空间电荷效应。我们发现，1纳米的顺序和低于10 fs的时间分辨率的空间分辨率将是可行的脉冲组成的平均20个电子。模拟了样品平面处横向电场的影响，表明可以分辨1 V μm-1，对应于每μm2 10 e的表面电荷密度，与光驱动电子学和超快纳米等离子体激元学中产生的场相当。这种仪器的实现预计将有助于在原子时间和长度尺度上对激光引发的物理，化学和生物结构动力学进行前所未有的阐明。
Recent developments in ultrafast electron microscopy have shown that spatial and temporal information can be collected simultaneously on very small and fast scales. In the present work, an instrumental design study with application to nanoscale dynamics, we optimize the conditions for a femtosecond transmission electron microscope (fs-TEM). The fs-TEM numerically studied employs a metallic nanotip source, electrostatic acceleration, magnetic lenses, a condenser-objective around the sample and a temporal compressor, and considers space-charge effects during propagation. We find a spatial resolution of the order of 1 nm and a temporal resolution of below 10 fs will be feasible for pulses comprised of on average 20 electrons. The influence of a transverse electric field at the sample plane is modelled, indicating 1 V μm-1 can be resolved, corresponding to a surface charge density of 10e per μm2, comparable to fields generated in light-driven electronics and ultrafast nanoplasmonics. The realisation of such an instrument is anticipated to facilitate unprecedented elucidation of laser-initiated physical, chemical and biological structural dynamics on atomic time- and length-scales.