High-Power Ferroelectric Switch for an X-Band RF Pulse Compressor

75185S High energy electron linear accelerators use microwave pulse compression to produce the high peak power levels needed to obtain high acceleration gradients. Present passive pulse compressors produce a power gain of about 3:1, in return for a 4:1 compression in pulse width. Active pulse compressors are predicted to have a capability for much larger compression ratios, with high efficiencies as well. Therefore, this project aims to develop a fast, ferroelectric X-band switch for activating a pulse compressor with the ability to switch several times during the input pulse, thereby allowing efficiency values >90%. In Phase I, computational techniques were used to refine the design of the ferroelectric switch, in order to minimize losses and thereby increase device efficiency. Fabrication techniques for large (10-cm diameter) ferroelectric rings were demonstrated, and a plan was formulated for testing high-power versions of the switch in the Naval Research Laboratory (NRL) magnicon facility. In Phase II, fabrication, sintering, and finishing techniques will be used to produce a quantity of ferroelectric rings needed for the switches. An engineering design for manufacturing the switches will be developed, and at least two switches will be built. The switches will be tested at NRL up to an input power level of 50 MW. Commercial Applications and Other Benefits as described by the awardee: Hundreds of active microwave switches could be used in a future multi-TeV linear collider, or other high-gradient room-temperature linear accelerator, representing a market of millions of dollars. Other commercial and military applications of rapid, efficient active switches using ferroelectrics at other frequencies and powers also exist, representing additional market potential.