A possible observation of quantum nucleation in superfluid He4near crystallization

✍ Scribed by V. L. Tsymbalenko

• Publisher: Springer US
• Year: 1992
• Tongue: English
• Weight: 805 KB
• Volume: 88
• Category: Article
• ISSN: 0022-2291
• DOI: 10.1007/bf00122558

✦ Synopsis

The overpressurization of superfluid He 4 under crystallization is studied experimentally. The effect of a substrate and He 3 impurities on the nucleation rate W is observed. The dependence of the metastable state lifetime versus the overpressurization and temperature is measured in the range 10-7-1 s and 0.52-1.75 K. The results are compared with the theoretical predictions for the classic and quantum nucleation. The surface relief effect is considered. It is shown that relative to a flat surface, a cone-shaped pit is a site corresponding to a smaller nucleation energy. In this case a change of the nucleation rate versus the metastability degree and temperature in the classic region is analyzed. As a result, the most reliable qualitative manifestation of quantum nucleation is the independence of the metastable degree under the constant rate W upon temperature, which is observed below 1 K in the experiment.