Space charge effects in ultrafast electron diffraction and imaging
- Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824-2320 (United States)
Understanding space charge effects is central for the development of high-brightness ultrafast electron diffraction and microscopy techniques for imaging material transformation with atomic scale detail at the fs to ps timescales. We present methods and results for direct ultrafast photoelectron beam characterization employing a shadow projection imaging technique to investigate the generation of ultrafast, non-uniform, intense photoelectron pulses in a dc photo-gun geometry. Combined with N-particle simulations and an analytical Gaussian model, we elucidate three essential space-charge-led features: the pulse lengthening following a power-law scaling, the broadening of the initial energy distribution, and the virtual cathode threshold. The impacts of these space charge effects on the performance of the next generation high-brightness ultrafast electron diffraction and imaging systems are evaluated.
- OSTI ID:
- 22036814
- Journal Information:
- Journal of Applied Physics, Vol. 111, Issue 4; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Visualizing lattice dynamic behavior by acquiring a single time-resolved MeV diffraction image
Future of Electron Scattering and Diffraction