The Kapitza conductance and its enhanced power anomaly for clean silver to helium-four interfaces at temperatures between 1 and 2 K
Abstract
Results are described of a detailed investigation of the Kapitza conductance of clean, high-purity, annealed and electropolished silver samples and helium-four at temperatures between 1 and 2 K. The values and the temperature dependence of the heat transfer coefficient for deep electropolished samples are in good agreement with the damped acoustic mismatch theory combined with a dense helium layer. A dependence of the heat transfer coefficient on the dislocation density near the interface is found in agreement with earlier results on copper. The enhanced power anomaly found before on copper is confirmed. Supercritical transitions are found separately for the bulk fluid and for the helium surface layer. A new anomaly is found when the surface layer temperature exceeds the lambda point. Transient times in the supercritical state are significantly longer than in the subcritical state, but much less than found for copper. Other effects are similar. The results are discussed in terms of localized heat transfer associated with impurities and dislocations near the interface.
- Publication:
-
Journal of Low Temperature Physics
- Pub Date:
- April 1980
- DOI:
- 10.1007/BF00118067
- Bibcode:
- 1980JLTP...39...93B
- Keywords:
-
- Heat Transfer Coefficient;
- Localize Heat Transfer;
- Supercritical State;
- Bulk Fluid;
- Layer Temperature