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Mrstik, Bernard Joseph 2012-02-02T20:22:12Z 2012-02-02T20:22:12Z 10000-01-01 1973 We have measured the thermal conductivity of several superconducting films. These films were evaporated onto substrates held at liquid helium temperatures, and therefore the phonon mean free path in these films was very short. Consequently, the phonons contributed very little to the thermal conductivity. The experimentally determined thermal conductivity was therefore due almost entirely to the conduction of heat by the electrons. The electron thermal conductivity Ke s of a strong-coupling superconductor and of superconductors containing rare earth impurities has been measured in this way. We have generalized the theoretical expression for Ke s of strong-coupling superconductors to include elastic scattering of the electrons. When elastic scattering of the electrons dominates,the expression for K es reduced to that of. Bardeen, Rickayzen, and Tewordt, except for a change in the energy gap width, These results are in good agreement with our experimental measurements on a quench-condensed film of lead. We have also measured the thermal conductivity of thin films of lead or indium containing small amounts of gadolinium, These results are in good agreement with theoretical results of Ambegaokar and Griffin (modified for strong-coupling effects), except at very low temperatures. We believe that the low temperature deviations are related to the properties of the substrate, rather than to the characteristics of the superconducting films. Submitted by Megan O'Donnell (mnodonn2@illinois.edu) on 2012-02-02T20:22:12Z No. of bitstreams: 1 1973_mrstik.pdf: 4462568 bytes, checksum: 158b83d882bbe548e8adf6309cd00979 (MD5) Made available in DSpace on 2012-02-02T20:22:12Z (GMT). No. of bitstreams: 1 1973_mrstik.pdf: 4462568 bytes, checksum: 158b83d882bbe548e8adf6309cd00979 (MD5) Previous issue date: 1973 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Megan O'Donnell (mnodonn2@illinois.edu) on 2012-02-02T20:22:12Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:10:04-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: thesis/dissertation thesis/dissertation U of I Only 2516869 http://hdl.handle.net/2142/29598 en © 1973 Bernard Joseph Mrstik Thin films rare earth impurities in metals superconducting films Electron thermal conductivity of thin films of strong-coupling superconductors and of superconductors containing rare earth impurities Dissertation / Thesis text Physics Physics University of Illinois at Urbana-Champaign Dissertation Ph.D.