High performances from a GaAs photoemitter

This paper aims at collecting the experimental results we have obtained ahout a GaAs photocathode, activated in negative affinity condition by depositing a thin layer of caesium and oxygen al its surface

Very-high-resolution energy analyser for electron beams

The authors designed an energy analyser for electron beams which exploits the retarding potential method over a small portion of the beam when all relaxations in the beam have occurred. This permits great improvement of energy resolution with respect to standard devices. The resolution depends on beam energy and is in the range 5-7 meV. The authors applied the energy analyser to determine the temperature dependence of the energy spread for electron beams emitted from GaAs

Low energy intense electron beams with extra-low energy spread

Maximum achievable intensity for lowenergyelectronbeams is a feature that is not very often compatible with lowenergyspread. We show that a proper choice of the source and the acceleration optics allows one to match them together. In this scheme, a GaAs photocathode excited by a single-mode infrared laser and adiabatic acceleration in fully magnetised optics enables the production of a low-energy-spreadelectronbeam with relatively high intensity. The technological problems associated with the method are discussed together with its limitations