Direct visualization of electromagnetic wave dynamics by laser-free ultrafast electron microscopy

被引：36

作者：

Fu, Xuewen ^{[1
,2
]}

Wang, Erdong ^{[3
]}

Zhao, Yubin ^{[4
]}

Liu, Ao ^{[4
]}

Montgomery, Eric ^{[4
]}

Gokhale, Vikrant J. ^{[5
]}

Gorman, Jason J. ^{[5
]}

Jing, Chunguang ^{[4
]}

Lau, June W. ^{[6
]}

Zhu, Yimei ^{[1
]}

机构：

[1] Brookhaven Natl Lab, Condensed Matter Phys & Mat Sci Dept, Upton, NY 11973 USA

[2] Nankai Univ, Sch Phys, Tianjin 300071, Peoples R China

[3] Brookhaven Natl Lab, Collider Accelerator Dept, Upton, NY 11973 USA

[4] Euclid Techlabs LLC, 365 Remington Blvd, Bolingbrook, IL 60440 USA

[5] NIST, Microsyst & Nanotechnol Div, Gaithersburg, MD 20899 USA

[6] NIST, Mat Sci & Engn Div, Gaithersburg, MD 20899 USA

来源：

SCIENCE ADVANCES | 2020年 / 6卷 / 40期

关键词：

Electron microscopes - Electrons - Circular waveguides - Femtosecond lasers - Electromagnetic fields - Electromagnetic wave propagation - Pulse repetition rate - Electron microscopy - Visualization;

D O I：

10.1126/sciadv.abc3456

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Integrating femtosecond lasers with electron microscopies has enabled direct imaging of transient structures and morphologies of materials in real time and space. Here, we report the development of a laser-free ultrafast electron microscopy (UEM) offering the same capability but without requiring femtosecond lasers and intricate instrumental modifications. We create picosecond electron pulses for probing dynamic events by chopping a continuous beam with a radio frequency (RF)-driven pulser with the pulse repetition rate tunable from 100 MHz to 12 GHz. As a first application, we studied gigahertz electromagnetic wave propagation dynamics in an interdigitated comb structure. We reveal, on nanometer space and picosecond time scales, the transient oscillating electromagnetic field around the tines of the combs with time-resolved polarization, amplitude, and local field enhancement. This study demonstrates the feasibility of laser-free UEM in real- space visualization of dynamics for many research fields, especially the electrodynamics in devices associated with information processing technology.

引用

页数：8