相关论文: Sub-nanosecond Electron Emission from Electrically…

The properties of the electron source define the ultimate limit of the beam quality in linear accelerators like Free Electron Lasers (FEL). The goal is to develop an electron gun delivering beam emittance lower than current state of the…

GeAs is a layered material of the IV-V groups that is attracting growing attention for possible applications in electronic and optoelectronic devices. In this study, exfoliated multilayer GeAs nanoflakes are structurally characterized and…

In the framework of the Low Emittance Gun (LEG) project, high gradient acceleration of a low emittance electron beam will be necessary. In order to achieve this acceleration a -500 kV, 250 ns FWHM, pulse will be applied in between two…

We describe and discuss solutions for an innovating sub-relativistic electron source, based on pulsed DC gun, including linear (1D) Field Emitter Array (FEA) associated immediately with Laser Dielectric Accelerator (DLA) stage. That setup…

Field-emission of electrons underlies major advances in science and technology, ranging from imaging the atomic-scale structure of matter to signal processing at ever-higher frequencies. The advancement of these applications to their…

Nanosecond electron pulses are appealing for ultrafast imaging and electron gating applications, where tunable currents and narrow energy spreads are desirable. Here, we demonstrate photoemission from a Schottky emitter triggered by…

High peak and average power free-electron lasers (FELs) in the terahertz region (THz) require small diameter, low-emittance, and high voltage electron beams. This paper presents two 1.5-2 MV, 100-200 A, thermionic cathode electron source…

Radiofrequency (RF) electron guns operating at high accelerating gradients offer a pathway to producing bright electron bunches. Such beams are expected to revolutionize many areas of science: they could form the backbone of next-generation…

We find that, under appropriate conditions, electrons can pass a barrier etched across a two dimensional electron gas (2DEG) by field emission from the GaAs/AlGaAs heterojunction into a second, low-density 2DEG formed deep in the substrate.…

A pulsed electron gun that can produce MHz repetition rate nanosecond pulses is described. The gun uses a Pierce grid in combination with an anode to extract electrons from a tungsten filament cathode. The electrons emerging from the anode…

Recent studies have demonstrated the possibility of accelerating electrons to MeV energies in ambient air using tightly focused laser configurations. In this article, we explore possible strategies to control and optimize the resulting…

Ultrafast transmission electron microscopy (UTEM) has emerged as a versatile technique for the time-resolved imaging of nanoscale dynamics on timescales down to few-hundred attoseconds but the temporal and spatial resolutions are still…

In this Letter we report on the experimental generation of high energy (10 GeV), ultra-short (fs-duration), ultra-high current (0.1 MA), petawatt peak power electron beams in a particle accelerator. These extreme beams enable the…

Particle accelerators are essential tools in science, hospitals and industry. Yet, their costs and large footprint, ranging in length from meters to several kilometres, limit their use. The recently demonstrated nanophotonics-based…

The operation of Ultrafast Electron Diffractometers (UEDs) and Free-Electron Lasers (FELs) relies on high-brightness electron beams produced by radio-frequency (RF) photocathode guns. The next generation of high-repetition rate UEDs and…

The guiding and control of ultrahigh flux, femtosecond relativistic electron pulses through solid density matter is of great importance for many areas of high energy density science. Efforts so far include the use of magnetic fields…

Nanoelectronic devices embedded in the two-dimensional electron system (2DES) of a GaAs/AlGaAs heterostructure enable a large variety of applications from fundamental research to high speed transistors. Electrical circuits are thereby…

Free-electron lasers (FELs) operate at wavelengths from millimeter waves through hard x-rays. At x-ray wavelengths, FELs typically rely on self-amplified spontaneous emission (SASE). Typical SASE emission contains multiple temporal "spikes"…

It is shown that focusing circularly-polarized 800 nm light pulses of 100 fs duration on the tips of p-GaAs crystalline shards having no negative electron affinity (NEA) activation results in electron emission that is both fast and…

We study the emission of femtosecond spin current pulses at Fe/Au interfaces. Using optical second harmonic generation we demonstrate the control of pulse shape and duration by varying the emitter thickness and show that it is determined by…