Superconducting resonator for high frequency - high power applications

Superconducting helical resonators operating in the HF band at approximately 16 MHz have been designed and constructed to demonstrate the feasibility of passing a kilowatt of power at an operation Q of 1000 (QDL= 1000). Superconducting components are being considered to replace normal state circuits in communication systems, i.e. antennas and multicouplers. (A multicoupler is a device using coupled resonators which permits a number of transmitters to be simultaneously operated into one antenna.) The niobium helical resonators were polished and anodized after being fabricated using an electron-beam welding process. Teflon support structures were designed to minimize vibrational problems. The resonator was operated open to the helium bath and the resulting unloaded Q was in excess of 4×10⁶. A kilowatt of power was transferred through the resonator when operating at a QDLof 1000. Work is now proceeding on the design and fabrication of a tunable resonator.