Superconducting Resonant Cavities

Abstract

Superconducting cavities offer a means of obtaining extremely high Q resonators not easily available by other techniques at microwave frequencies. During the past fifteen years, a body of data has been accumulated on the microwave surface resistance and reactance of a few superconductors over almost the entire microwave spectrum. Resonant cavity techniques have been employed in many of these investigations. In these experiments the emphasis was not usually on designing cavities to obtain extraordinarily Mgh Q’s since in many experiments the high Q increases the difficulty of the measurement. Nevertheless, the data now available is directly applicable to the problem of designing high Q resonant cavities. In the following discussion, we shall review the basic physical principles, summarize some of the pertinent experimental data and discuss some of the practical problems of design and fabrication.

Operated with support from the U.S. Army, Navy, and Air Force.