Experimental and Modeling Methods for Development of Diamond Electron Amplifiers

High-average current and high-brightness electron beams are needed in advance applications such as ultra-high power Free-Electron Lasers (FELs) and electron accelerators. The technologically important material properties of diamond are of significant interest for development of electron emission, detector, and wide-bandgap semiconductor applications, including radiation-hard devices. A diamond amplifier cathode concept has been proposed to generate such high average current electron beams. Experiments have already demonstrated the potential to generate amplified electron beams from diamond with peak current density greater than 400 mA per square mm and average current density larger than 100 mA per square mm. However, the concept is still to be fully developed and tested in accelerator cavities. Moreover, the optimal surface preparation is still to be determined. We propose to address this problem by fabrication of diamond amplifier samples with different surface properties, experimental testing, and high-fidelity modeling to assist the experimental work.