Free Electron Maser for High Power THz Generation

Abstract

The THz technology gap in the electromagnetic spectrum provides for a large interest in exploring possibilities to close this gap with new sources, detectors and amplifiers. Two different approaches exist, creating microwave devices for higher and higher frequencies, or lowering the frequency from optical equipment. This thesis shows design and computer simulations of a compact free electron maser (FEM) with high output power. The size of the FEM is equivalent to a standard optical table found in most optical laboratories around the world, which is much more portable than regular free-electron systems. Using the computer codes SUPERFISH, Parmela and WIGGLIN, we have shown peak powers in the order of several megawatt and average powers of tens of kilowatts for frequencies between 0.24THz and 0.34THz. This bandwidth is limited by waveguiding effects in the permanent magnet structure in the end of this FEM.