Specific Heat of the Surface Layers on the Amorphous Substrate in Solid and Liquid 3He

Abstract

We have observed an excess heat capacity in liquid and bcc solid 3He at low temperatures. The heat capacity in the normal fluid is found to be the sum of the heat capacity of bulk normal fluid and a temperature-independent heat capacity ΔC due to amorphous solid layers on the silver sinter surface, where ΔC=7.3±6.8 μJK−1m−2 corresponds to 1.6±0.6 amorphous solid layers. The heat capacity for bcc solid 3He is the sum of the heat capacity originating from the multiple-exchange interaction and a temperature independent heat capacity. The excess heat capacity ΔC=12.1±3.1 μJK−1m−2 for bcc solid corresponds to 1.9±0.3 amorphous solid layers. Our result indicates that the amorphous solid layers on an amorphous substrate yield a universal ΔC in unit area throughout liquid, solid and adsorbed 3He.