Titanium Nitride (TiN) has recently garnered much interest as a potential photocathodic material with superior properties to conventional materials [1]. TiN thin films can be grown on various substrates using magnetron sputtering or vapour deposition techniques. However, these require an existing sputter target or powder of high-quality TiN. This study presents a molecular beam epitaxy...
Photo-electron sources utilizing GaAs-based photocathodes are used to provide high-brightness and high-current beams of possibly spin-polarized electrons for accelerator applications such as free-electron lasers (FELs) and energy recovery linacs (ERLs). These cathodes require a thin surface layer consisting of cesium and an oxidant in order to achieve negative electron affinity (NEA) for...
In an Energy Recovery Linac (ERL), the beam, after acceleration and interaction, is recirculated and decelerated in the accelerating cavities of the linac. In such a scheme, the energy of the beam is recovered, leading to substantial savings in electrical power. Moreover, the beam is dumped at injection energy, considerably simplifying the radioprotection of the facility. The PERLE project...
At the new, energy-recovering superconducting accelerator MESA in Mainz, spin-polarised electrons are required in the P2 experiment. Here the requirements increase considerably compared to the experiments at the micotron MAMI in Mainz.
A very sensitive part of the photocathodes lies in the specially prepared surface, characterised by its negative electron affinity. This surface is highly...
The Photoemission and Bright Beams Lab at ASU performs experimental and theoretical research to develop a fundamental understanding of light-matter interactions as relevant to the photoemission process with the goal of developing advanced electron sources for electron microscopy, ultrafast science, and nuclear and high energy physics. We employ the smoothest of atomically ordered surfaces at...
Cesium telluride (Cs-Te) photocathodes are widely used as an electron source in photoinjectors due to their high quantum efficiency (QE) and reliable performance. Unfortunately, they are chemically highly reactive, which limits their operational lifetime and require frequent interventions for Cs-Te film replacement or rejuvenation. The precise control of the Cs-Te deposition stoichiometry...
Modern advances in generating ultrabright electron beams have enabled significant experimental progress using synchrotron radiation. Current challenges include improving the quality of electron sources with novel photocathode materials such as alkali-based semiconductors. To fully harness their potential, a detailed characterization and prediction of their fundamental properties are essential....
