Accession Number:

ADA001106

Title:

Experimental Studies of the Microwave Properties of 8.6 GHz Superconducting Niobium, Niobium-Tantalum, and Tantalum Cavities.

Descriptive Note:

Doctoral thesis,

Corporate Author:

STANFORD UNIV CALIF HIGH ENERGY PHYSICS LAB

Personal Author(s):

Report Date:

1974-09-01

Pagination or Media Count:

130.0

Abstract:

In this dissertation measurements on the surface impedance of superconducting niobium, tantalum, and a 30 at niobium-70 at tantalum alloy are reported. The measurements were made on X-band mode cavities at a nominal frequency of 8.6 GHz. The surface resistance and the change of surface reactance for the three materials were measured from 1.3 K up to their respective transition temperatures. These data were compared to computer calculations based on the Mattis-Bardeen expressions for the surface resistance and reactance of superconductors. Evidence is also presented concerning the effect of thermal expansion of niobium on the resonant frequency of an X-band cavity as a function of temperature below 2K. The influence of trapped magnetic flux on the microwave surface resistance and reactance of niobium is also reported. Modified author abstract

Subject Categories:

  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE