具有相对论飞秒电子脉冲的超快电子显微镜。

Ultrafast electron microscopy with relativistic femtosecond electron pulses.

作者信息

Yang Jinfeng, Yoshida Yoichi, Yasuda Hidehiro

机构信息

The Institute of Scientific and Industrial Research (ISIR), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, Japan.

Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka, Japan.

出版信息

Microscopy (Oxf). 2018 Oct 1;67(5):291-295. doi: 10.1093/jmicro/dfy032.

DOI:10.1093/jmicro/dfy032

PMID:29992251

Abstract

Ultrafast electron microscopy (UEM) with femtosecond temporal resolution is a 'dream machine' that has been long envisioned for the study of ultrafast structural dynamics in materials. For this purpose, we developed a prototype UEM with relativistic femtosecond electron pulses generated by a radio-frequency acceleration-based photoemission gun. TEM images of polystyrene latex particles and gold nanoparticles were observed using approximately 100-fs-long electron pulses with energies of 3.1 MeV. The effect of emittance and the number of pulses on the images were investigated. We demonstrated single-shot imaging with the femtosecond electron pulse at low magnification of approximately 500×.

摘要

具有飞秒时间分辨率的超快电子显微镜（UEM）是一台长期以来被设想用于研究材料中超快结构动力学的“梦幻机器”。为此，我们开发了一种原型UEM，它利用基于射频加速的光发射枪产生相对论飞秒电子脉冲。使用能量为3.1 MeV、脉宽约100 fs的电子脉冲观察了聚苯乙烯乳胶颗粒和金纳米颗粒的透射电子显微镜（TEM）图像。研究了发射度和脉冲数对图像的影响。我们展示了在约500倍的低放大倍数下用飞秒电子脉冲进行的单次成像。