Subparticle ultrafast spectrum imaging in 4D electron microscopy.
Single-particle imaging of structures has become a powerful methodology in nanoscience and molecular and cell biology. We report the development of subparticle imaging with space, time, and energy resolutions of nanometers, femtoseconds, and millielectron volts, respectively. By using scanning electron probes across optically excited nanoparticles and interfaces, we simultaneously constructed energy-time and space-time maps. Spectrum images were then obtained for the nanoscale dielectric fields, with the energy resolution set by the photon rather than the electron, as demonstrated here with two examples (silver nanoparticles and the metallic copper-vacuum interface). This development thus combines the high spatial resolution of electron microscopy with the high energy resolution of optical techniques and ultrafast temporal response, opening the door to various applications in elemental analysis as well as mapping of interfaces and plasmonics.
Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA.
Aycan
A
Yurtsever
Renske M
RM
van der Veen
Ahmed H
AH
Zewail
D003300:Copper; D008027:Light; D053768:Metal Nanoparticles; D008854:Microscopy, Electron / Q000379:methods; D017785:Photons; D012834:Silver; D013995:Time; D014618:Vacuum
D012834:Silver; D003300:Copper