Research is planned to make new advances in mm-and sub-mm wave sources, as well as their applications. This work will be based on prior experience in developing mm-wave Free Electron Laser devices at reduced beam voltages (both high power 0.5-1.0 MV FEL oscillators and 50 kV harmonic "ubitron" amplifiers). The new directions, however, will emphasize studies of compact, "low" voltage (< 100 kV), and moderate power (0.1-100 kW) devices to be compatible with commercially practical civilian and government applications. To accomplish new developments in this field, research innovations in electron beam generation and focusing techniques, small-scale radiation cavities and periodic structures, and nonlinear efficiency enhancement and mode control techniques will be carried out. Also research on compact periodic structures as an opportunity to research, develop, and perform (scaled) testing of new insertion devices for high energy electron storage rings will be performed. Such insertion devices should extend the capabilities of U.S. storage ring facilities as high brightness IR, VUV, and x-ray light source facilities for spectroscopic, materials science, lithographic, and biomedical applications. Finally, in addition to the ceramic sintering process, there are several new applications for moderate power mm-wave sources such as, mm-wave heating of a compact, high density, mirror plasma to efficiently generate soft x-rays for lithography and materials processing applications. Another interest is to study the use of mm-waves for improved thermal processing of dielectric coatings. A third area of interest would be the previously mentioned use of coherent sub-mm sources, (i.e., wavelengths between 0.01-1.0 mm) for spectroscopy of various chemical chain reactions and solid-state semi-conductor phenomena.
