Femtosecond Time-resolved MeV Electron Diffraction
Abstract
We report the experimental demonstration of femtosecond electron diffraction using high-brightness MeV electron beams. High-quality, single-shot electron diffraction patterns for both polycrystalline aluminum and single-crystal 1T-TaS2 are obtained utilizing a 5 femto-Coulomb (~3x10^4 electrons) pulse of electrons at 2.8 MeV. The high quality of the electron diffraction patterns confirm that electron beam has a normalized emittance of ~50 nm-rad. The corresponding transverse and longitudinal coherence length are ~11 nm and ~2.5 nm, respectively. The timing jitter between the pump laser and probe electron beam was found to be ~ 100 fs (rms). The temporal resolution is demonstrated by observing the evolution of Bragg and superlattice peaks of 1T-TaS2 following an 800 nm optical pump and was found to be 130 fs. Our results demonstrate the advantages of MeV electron diffraction: such as longer coherent lengths, large scattering cross-section and larger signal-to-noise ratio, and the feasibility of ultimately realizing 10 fs time-resolved electron diffraction.
Cite
@article{arxiv.1304.5176,
title = {Femtosecond Time-resolved MeV Electron Diffraction},
author = {Pengfei Zhu and H. Berger and J. Cao and J. Geck and Y. Hidaka and R. Kraus and S. Pjerov and Y. Shen and R. I Tobey and Y. Zhu and J. P. Hill and X. J. Wang},
journal= {arXiv preprint arXiv:1304.5176},
year = {2014}
}