4D Electron Microscopy
We have established and developed the second generation of four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM) and demonstrate the ability to record time-resolved images (snapshots) of material surfaces with 650 fs and ~ 5 nm temporal and spatial resolutions, respectively.
Using S-UEM, we spatially and temporally visualize the charge carrier dynamics on the surface of InGaN NW arrays before and after surface passivation with octadecylthiol (ODT).
Here, we precisely map the surface charge carrier dynamics of the CIGS before and after surface passivation in space and time.
By visualizing different surface of CdSe single crystals, we show that the morphology, grains and nanostructure features of the material surface can impact the overall carrier relaxation processes.
Using our S-UEM with a 650 fs and ~5 nm temporal and spatial resolutions, respectively, we show that time resolved imaging of the energy loss dynamics and carrier spreading on the surfaces of a densely packed array of InGaN nanowires (NWs) as a model system can be achieved now in real space.