Heat capacity and pressure at phase separation and solidification of 3HE in HCP 4HE

Abstract

Abstract We have measured heat capacity and pressure of 0.45 % and 0.9 % 3 He 4 He mixtures at pressures between 27 bar and 33 bar and temperatures between 18 mK and 300 mK. The data show the latent heats and the pressure changes associated with the solid phase separation (or remixing) and with the liquification (or solidification) of the resulting 3 He droplets in the hcp 4 He matrix. These data as well as the heat capacity of the liquid 3 He droplets show that all 3 He phase-separates, but only part of it liquifies. The amount of liquid depends on the history of the experiment.