Nucleation of transitions in liquid 3He--4He mixtures

We present a complete set of data describing the nucleation both of superfluidity and phase separtion at container walls in liquid 3He--4He mixtures. The appearance of superfluidity and the growth of phase-separated films are measured locally at the walls. A theoretical interpretation is given, important results of which are that the phase separation and superfluid transitions become uncoupled when the transitions are localized near the walls and that quantum fluctuations most probably strongly affect the nature of the superfluid nucleation transition at low temperature. Further, comparison of our results with data for transitions in pure 4He films demonstrates that a universality principle governs the transitions in both systems