Watching charge separation in nanoantennas by ultrafast point-projection electron microscopy
Abstract
Watching the motion of electrons on their natural nanometre length- and femtosecond time scales is a fundamental goal and an open challenge of contemporary ultrafast science. Optical techniques and electron microscopy currently mostly provide either ultrahigh temporal or spatial resolution, yet, microscopy techniques with combined space-time resolution need further development. Here we create an ultrafast electron source by plasmon nanofocusing on a sharp gold taper and implement this source in an ultrafast point-projection electron microscope. This source is used, in an optical pump - electron probe experiment, to study ultrafast photoemission from a nanometer-sized plasmonic antenna. We show that the real space motion of the photoemitted electrons and residual holes in the metal is probed with 20-nm spatial resolution and 25-fs time resolution. This is a step forward towards time-resolved microscopy of electronic motion in nanostructures.
Keywords
Cite
@article{arxiv.1801.06662,
title = {Watching charge separation in nanoantennas by ultrafast point-projection electron microscopy},
author = {Jan Vogelsang and Germann Hergert and Dong Wang and Petra Groß and Christoph Lienau},
journal= {arXiv preprint arXiv:1801.06662},
year = {2018}
}