High power THz technologies using high frequency gyrotrons

Gyrotrons are extremely high power radiation sources even in THz frequency region comparing conventional radiation sources. We have developed gyrotron FU CW series for application to many high power THz technologies. Up to the present, nine CW gyrotrons were developed. Each gyrotron has its own objective and was optimized for respective application subject. Now, the applications are extended to wide fields including DNP-NMR measurement, ESR echo experiment, direct and precise measurement on hyperfine structure of positronium, experiment on effective operation of Bloch oscillator using semiconductor super lattice, etc. In this paper, we will introduce such high power THz technologies opened by high power THz radiation sources. Gyrotrons.