Accession Number : AD0713242

Title :   DIAMAGNETISM DUE TO FLUCTUATIONS IN SUPERCONDUCTORS.

Descriptive Note : Technical rept.,

Corporate Author : HARVARD UNIV CAMBRIDGE MASS DIV OF ENGINEERING AND APPLIED PHYSICS

Personal Author(s) : Gollub,Jerry P.

Report Date : SEP 1970

Pagination or Media Count : 193

Abstract : Fluctuations of the order parameter above T sub c in superconductors give rise to a small diamagnetism, comparable in magnitude to the Landau diamagnetism. An extremely sensitive magnetometer system was devised to measure this small temperature-dependent diamagnetism. A superconducting quantum interference device coupled to the sample was used as a magnetic flux detector. The sample temperature could be varied continusously between 2 K and 16 K while magnetization changes as small as 10 to the - 8th power gauss were resolved. Extensive measurements have been performed on bulk single crystals of three materials: indium, lead, and type II lead-thallium alloys. Each of these materials shows a temperature-dependent diamagnetism which is qualitatively described by Prange's calculation for small applied fields. Results are discussed.

Descriptors :   (*SUPERCONDUCTORS, MAGNETIC PROPERTIES), TRANSITION TEMPERATURE, MAGNETOMETERS, THALLIUM ALLOYS, LEAD ALLOYS, LEAD(METAL), INDIUM

Subject Categories : Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE