Accession Number : AD0433473

Title :   SUPERCONDUCTIVE FREQUENCY CONTROL DEVICES.

Descriptive Note : Rept. no. 4 (Final), 30 June 62-1 Sep 63,

Corporate Author : ELECTRONIC MATERIALS RESEARCH LAB UNIV OF TEXAS AUSTIN

Personal Author(s) : Hartwig,William H.

Report Date : 01 SEP 1963

Pagination or Media Count : 149

Abstract : Surface impedance theories and experimental results are examined. The quantum mechanical approach gives curves having the right general shape with temperature and frequency. They are inferior to the phenomenological approach in accuracy, however. The quantum approach is most useful at high frequencies. The most attractive theory seems to be the one developed by Dresselhaus and Dresselhaus. Theoretical equations and experimental data are presented for comparison. DC superconductive properties of Lead-Tin alloy foils are presented. Critical temperature remains near 7.2 K until lead concentration falls below 20%. In a magnetic field the alloys have type II behavior with higher critical field and broader resistive transitions. Impurities in 100% Lead are very critical in determining resistivity since this metal tends to be selfannealing. Circuit configurations discussed include helical resonators, foil wound on quartz, and thin films. Electroplating lead is described. (Author)

Descriptors :   (*TUNED CIRCUITS, SUPERCONDUCTORS), (*SUPERCONDUCTORS, TUNED CIRCUITS), TUNING DEVICES, SUPERCONDUCTIVITY, ELECTRICAL IMPEDANCE, LEAD ALLOYS, TIN ALLOYS, MAGNETIC FIELDS, IMPURITIES, QUARTZ, ELECTROPLATING, LEAD(METAL), TEMPERATURE, EQUATIONS, SOLENOIDS

Distribution Statement : APPROVED FOR PUBLIC RELEASE