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

75185-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 theoretically predicted to have a capability for much larger compression ratios, with high efficiencies as well. Therefore, this project will develop an active X-band pulse compressor with the ability to switch several times during the input pulse, thereby allowing efficiency values >90%, and to operate at the peak and average power levels anticipated for the Next Linear Collider. Ferroelectric elements will be introduced into resonant microwave cavities, with rapid switching effected by applying a pulsed high-voltage field across opposing faces of the ferroelectric. In Phase I, computational analyses will be used to optimize the design of an active microwave switch for an 11.424 GHz (the frequency for the Next Linear Collider) pulse compressor, based on use of ferroelectric elements in a two-cavity resonant structure. Parameters will be selected to correspond to advanced ferroelectric materials with low loss, moderate dielectric constant, and adequate voltage tenability. The optimized design will form the basis for a high-vacuum, high-power version of the switch to be tested during Phase II. Commercial Applications and Other Benefits as described by the awardee: Hundreds of active microwave switches could be used in Next Linear Collider, or in its future upgrade, representing a market of millions of dollars. Other commercial and military applications for rapid, efficient active switches using ferroelectrics at other frequencies and powers also exist, representing additional market potential.