Novel Ultra-High Power Microwave Isolators

RF isolators are highly desired for use with high-power RF sources and linear accelerator systems. However, the capabilities of RF sources, in terms of power, way exceed the available state-of-the-art circulators and associated loads. Furthermore, the available isolators are limited in terms of reliability and cost. There is no known way to extend their power handling capability or to improve their reliability. Our company, TibaRay, Inc., is an offshoot of SLAC. Our team proposes a new class of nonreciprocal devices with much higher power handling capabilities and scalability, in principle, to extremely high power levels. Furthermore, the devices are compact and promise low cost in production. Our concept for implementing these devices is based on a new development for a new microwave device by S. Tantawi at SLAC. His new invention and the associated topology would make it possible to create a modular structure that allows the synthesis of isolators and loads, in principle, for arbitrary power levels. Certainly, the idea has its limitations, but the limits appear to be very high. We will partner with S. Tantawi and his group at SLAC to industrialize these concepts and move them from highly specialized devices developed in a national laboratory to readily, commercially available devices for both industrial and scientific applications across the globe. In Phase I we plan to do electromagnetic and thermal calculations on the design of both S-band and X- band isolators and research on the best ferrite/garnet material to use in the circular waveguide. If approved and funded, in Phase II we plan to manufacture prototypes of the S-band and X-band circulator prototypes, plan for commercial production and develop relationship with potential clients. All medical linacs and linac- based security systems use RF isolators and the market is large, e.g. Varian Medical alone manufactures 500 such system a year. The current devices are not reliable and do not satisfy future needs. Our proposed isolator will be more reliable, capable of handling much higher powers and more economical to manufacture. Reducing the overall manufacture and operational costs of accelerators for medical, industrial and security applications and improving their reliability is key to more widespread applications of such systems, e.g. cargo scanning applications. Also, we hope to design isolators capable of 10’s of MW power handling capability which can be used in HEP accelerators.