Free electrons are central to such diverse applications as electron microscopes, accelerators, and photo-emission spectroscopy. However, space charge effects of many electrons are often problematic and, when confined to extremely small space-time dimensions, already two electrons can interact strongly. Here, we demonstrate that the resulting Coulomb repulsion can also be advantageous, as it...
The out-of-equilibrium dynamics of engineered nanoscale systems, such as moiré materials, is an important domain for ultrafast science. Ultrafast electron diffraction (with high-angular magnification) is especially suited to investigating spatially coherent normal modes of oscillation in these systems, collective motion that could hold the key to novel device functionality. Nanometer and...
The Ultra Cold Electron Source (UCES) being developed at Eindhoven University of Technology is based on near-threshold, femtosecond photoionization of a laser-cooled rubidium gas in a magneto-optical trap. The UCES accelerates bunches containing ~1000 electrons in a DC field up to energies of ~10 keV with a normalized emittance of ~1 nm·rad.
Recently, bunch lengths as short as 735±7 fs (rms)...
Ultrafast electron probing modalities offer unique experimental tools to access the structural dynamics of ultrafast photoinduced processes in materials and molecules, in liquid, gas, and condensed phase systems. Here we propose to capitalize on the exceptional and versatile electron beam parameters of the SEALAB Superconducting RF (SRF) photoinjector to develop a world-wide unique facility...
Imaging time-resolved molecular dynamics demands atto- to few-femtosecond temporal and picometer spatial resolution. Laser-induced electron diffraction (LIED) is a strong-field method based on coherent laser-driven scattering with one of the target's own electrons after photoionization. In this way, LIED differs from conventional ultrafast electron diffraction (UED) with external electron...
In this talk, I will discuss how the collective field of a relativistic electron beam can be used to instigate novel quantum dynamics and allow us to study ultrafast physics beyond typical laser-excited systems. At LCLS, the beam-supported fields can be shaped into strong (V/A), broadband (0-10 eV), and/or microbunched pulses that are intrinsically synchronized and mutually coherent with a...
RUEDI (Relativistic Ultrafast Electron Diffraction & Imaging) is a proposed UK national facility in the which will deliver single-shot, time-resolved, imaging with MeV electrons, and ultrafast electron diffraction down to 10 fs timescales. RUEDI is being designed to enable the following science themes: dynamics of chemical change; materials in ex-treme conditions; quantum materials; energy...
Mega-electronvolt ultrafast electron diffraction (MeV-UED) is a complementary tool to X-ray based instruments that has enabled ground-breaking studies in condensed matter physics and chemical science. A significant opportunity exists for MeV-UED beyond current instrument capabilities in quantum materials, microelectronics and photo-chemical research. Further improvement in MeV-UED transverse...
