相关论文: Simulation of short pulse photoemission in a micro…
We simulate numerically the classical charge dynamics in a microscopic, planar, vacuum diode with a finite emitter area and a finite number of electrons in the gap. We assume electrons are emitted under space-charge limited conditions with…
A new method of controllable injection to generate high quality electron bunches in the nonlinear blowout regime driven by electron beams is proposed and demonstrated using particle-in-cell simulations. Injection is facilitated by…
High resolution molecular dynamics simulations with full Coulomb interactions of electrons are used to investigate field emission in planar nanodiodes. The effects of space charge and emitter radius are examined and compared to previous…
An experimental and computational investigation of the space-charge effects occurring in ultrafast photoelectron spectroscopy from the gas phase is presented. The target sample CF$_3$I is excited by ultrashort (100 fs) far-ultraviolet…
We investigate the dynamics of a space-charge limited, photoinjected, electron beam in a microscopic vacuum diode. Due to the small nature of the system it is possible to conduct high-resolution simulations where the number of simulated…
We determine the limit of the lowest achievable photoemitted electron temperature, and therefore the maximum achievable electron brightness, due to heating just after emission into vacuum, applicable to dense relativistic or nonrelativistic…
Molecular dynamics simulations, with full Coulomb interaction and self-consistent field emission, are used to examine mutual space-charge interactions between beams originating from several emitter areas, in a planar infinite diode. The…
In an effort to increase spatial and temporal resolution of ultrafast electron diffraction and microscopy, ultra-high brightness photocathodes are actively sought to improve electron beam quality. Beam dynamics codes often approximate the…
We investigate intensity of the parametric down conversion of ultrashort, ultraviolet pulse both in a low- and high-conversion regime. In the first regime, we develop a simple analytical expressions for the photon flux of the fluorescence.…
In this work, we present the implementation of all-optical method for directly measuring electron pulse duration in an ultrafast scanning electron microscope. Our approach is based on the interaction of electrons with the ponderomotive…
Employing the linear sigma model, the effective masses of quasi-particle excitations are found to exhibit significant variations within the phase diagram, which has a critical point at non-zero chemical potential, where a first-order phase…
We demonstrate the generation of Coulomb-correlated pair, triple and quadruple states of free electrons by femtosecond photoemission from a nanoscale field emitter inside a transmission electron microscope. Event-based electron spectroscopy…
Recent experimental techniques in multicolor waveform synthesis allow the temporal shaping of strong femtosecond laser pulses with applications in the control of quantum mechanical processes in atoms, molecules, and nanostructures.…
Sources of high-energy photons have important applications in almost all areas of research. However, the photon flux and intensity of existing sources is strongly limited for photon energies above a few hundred keV. Here we show that a…
Today's high-intensity laser facilities produce short pulses can, in tight focus, reach peak intensities of $10^{22}\,\mathrm{Wcm}^{-2}$ and, in long focus, wakefield-accelerate electrons to GeV energies. The radiation-reaction--dominated…
We investigate by molecular dynamics simulations [arXiv:1412.4537 [physics.plasm-ph], arXiv:1608.06789 [physics.plasm-ph]] a beam of electrons released via field emission from a planar cathode surface of 1 ${\rm \mu m}^2$ with an…
The emission of a photon by an electron in an intense laser field is one of the most fundamental processes in electrodynamics and underlies the many applications that utilize high-energy photon beams. This process is typically studied for…
Reducing the intrinsic emittance of photocathodes is one of the most promising routes to improving the brightness of electron sources. However, when emittance growth occurs during beam transport (for example, due to space-charge), it is…
In this paper, electromagnetic emissions produced in a thin beam-plasma system are studied using two-dimensional particle-in-cell simulations. For the first time, the problem of emission generation in such a system is considered in the…
The electron beam dynamics in a nonmagnetized high-current vacuum diode is analyzed for different cathode-anode gap geometries. The conditions enabling to achieve the minimal {initial} momentum spread in the electron beam are found out. A…