Ultrafast photoemission electron microscopy: Capability and potential in probing plasmonic nanostructures from multiple domains

摘要

The near-field properties and dynamics of plasmonic nanostructures play a crucial role in several fundamental concepts in physics and chemistry, and they are widely relevant in plasmonic applications. Ultrafast photoemission electron microscopy (PEEM) is a novel approach that has been widely applied to probe plasmonic nanostructures from multiple domains. Furthermore, PEEM is the only technique that provides nanometer spatial resolution, sub-femtosecond temporal resolution, and tens to hundreds of millielectron volt energy resolution. This allows for extremely sensitive observations of plasmonic field oscillations, field dephasing, and hot electrons. This Perspective provides a brief overview of the basic principles and main applications of ultrafast PEEM. The research progress of ultrafast PEEM in plasmonics is highlighted from three points of view: near-field imaging, near-field spectroscopy, and ultrafast dynamics. Future applications of PEEM in plasmonics for the probing of plasmonic hot electron dynamics in the energy and time domains are proposed and discussed. (c) 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).