SUPERCONDUCTING PROPERTIES OF TIN, INDIUM, AND MERCURY BELOW 1 KELVIN
The critical field curves of superconducting tin, indium, and mercury were measured from T/sub c/ to 0.3 deg K. The measurements extend to sufficiently low temperatures to reach the region where the superconducting state entropy is negligible compared to the normal state entropy. From measurements in this low temperature range the normal electronic specific heat coefficient, gamma , was determined. The superconducting entropy and specific heat derived from the data are presented. The data were compared with the theory of Bardeen, Cooper, and Schrieffer in two ways: values of the energy gap at T = 0, 2 DELTA (0), derived from the measured values of H/sub 0/ and gamma were compared with the theoretical value of 3.52 kT/sub c/, and the temperature dependence of the measured critical field curves was compared with theoret1cal predictions. In addition, comparison was made between the measured critical field curves and curves obtained by scaling the BCS energy gap by a constant factor. Reasonable values of 2 DELTA (0) were obtained, but the full range of superconducting state behavior does not completely agree with theoretical predictions. Near T = T/sub c/ the energy gap derived from the critical field data rose more rapidly than would be predicted by scaling the BCS energy gap by the constant factor, 2 DELTA (0)/3.52 kT/sub c/. Results of the critical field measurements were compared with recent calorimetric data for tin and indium.
- Research Organization:
- Univ. of Illinois, Urbana
- NSA Number:
- NSA-16-033596
- OSTI ID:
- 4763940
- Journal Information:
- Dissertation Abstr., Vol. Vol: 23; Other Information: Orig. Receipt Date: 31-DEC-62
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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