Frost-heave phenomena ofHe4on porous glasses

We observed the frost-heave phenomena of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ on porous glasses. The static property of the frost heave was mainly studied, where the pressure jump across the boundary between bulk solid and liquid in the pores was measured in equilibrium as a function of the amount of supercooling of liquid in the pores from the bulk melting temperature. These measurements were performed at several constant pressures in the range 26–60 bars and at temperatures above 1.3 K. The results obtained above 28.5 bars were in good agreement with the modified Clausius-Clapeyron equation deduced by assuming that the chemical potential in the solid and liquid phase is the same. When the pressure was below 28 bars, the measured maximum frost-heave pressure became less than the prediction of the modified Clausius-Clapeyron equation. For a sample at 26.1 bars almost no indication of the frost-heave effect was observed.