Accession Number : AD0680919

Title :   CALORIMETRIC MEASUREMENT OF NEGATIVE SURFACE ENERGY IN SUPERCONDUCTORS OF THE SECOND KIND.

Descriptive Note : Final rept. 1 Sep 65-31 Dec 68,

Corporate Author : MISSOURI UNIV ROLLA

Personal Author(s) : Hopkins,Don C.

Report Date : 1968

Pagination or Media Count : 5

Abstract : The experimental details of this study are covered in the Ph.D. Thesis of Robert R. Riche entitled: 'A Calorimetric Study of the Effects of Surface Energy in a type II Superconductor.' The entropy of the mixed state of type II superconductors has been investigated experimentally. The results have been interpreted in terms of the interaction of quantized fluxoids (near H sub c1) or solutions of the Ginsburg-Landau equations (near H sub c2) instead of the negative surface energy model of the original proposal. One of the experimental methods used was a direct calorimetric measurement of the head added to hold the sample at a constant temperature as the magnetic induction was increased. An accurate technique for determining the thermodynamic critical field for an irreversible sample was also a contribution of this work. (Author)

Descriptors :   (*SUPERCONDUCTORS, *THERMODYNAMICS), SURFACE PROPERTIES, CALORIMETRY, SPECIFIC HEAT, ENTROPY, MAGNETIC FIELDS

Subject Categories : Electricity and Magnetism
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE