Spatiotemporal Visualization of the Acoustic Vibration of Plasmonic Single Nanorods Using Ultrafast Electron Microscopy

Abstract

With advances in spatial resolution reaching the atomic scale, 2 and 3 dimensional (D) imaging in transmission electron microscophy (TEM) has become an essential methodology in various fields of research providing static structural information. Now it has become possible to integrated the ultra temporal resolution (fourth dimension) to the 3D spatial resolution of TEM. Here, presented is the concept and recent in possible to directly visualize a single gold nanorod (Au NR) undergoing plsmonic-aeoustic vibration of sub-nanometer amplitude and picosecond period, upon femtosecond-plused light excitation for the first time. Tje unique integration of a direct electron detection camera to ultrafast electron beam enabled the unprecedented spatiotemporal resolutions with selective and characteristic vibrations of a single Au NR being unveiled in contrast to conventional optical spectroscopic measurements on ensembles.