High Performance Permanent Photocathodes

High performance, high brightness photocathodes are a critical enabling technology for ultrafast, high brightness DOE electron accelerators, such as the X-ray free electron laser FEL) at SLAC and MaRIE planned for Los Alamos National Laboratory, and for high-resolution electron microscopes at DOE material research centers. A novel approach to manufacturing nitride semiconductor materials will be developed and applied to produce intense photocathode technology that will advance the science of the study of high energy density plasmas, as well as research in materials science, physics, biology, and chemistry. Kyma will maximize beam current and minimize the mean transverse energies in novel Group III-Nitride based photocathodes by taking advantage of the pulsed sputter deposition technique to achieve unrealized doping control and smoothness in photocathode devices, giving rise to high quantum efficiencies and low mean transverse energy. In Phase I Kyma will utilize pulsed sputtering to create doped layers and heterostructures which will bode well for producing economical, environmentally robust, bright photocathodes. The research to be performed under this program will facilitate ultra-high performance and cost- effective radiation detection devices, which will find applications in quantifying radiation yields in a variety of nuclear experiments including Underground Nuclear Test, Advanced Radiography, Inertial Confinement Fusion, Device and Dynamic Material Properties, and other campaigns within Stockpile Stewardship and Nonproliferation programs. The ability to use pulsed sputtering to produce the materials for the photomultipliers has enormous ramifications for application to most if not all Group III- Nitride devices, including LEDs, laser diodes, power electronics, and high frequency electronics.