Observations of Homogeneous Phase Separation in LiquidHe3-He4Mixtures

Abstract

This Letter describes the physical behavior of superfluid dispersions created by pressure quenching ${}_{}{}^3{}_{}{}^{}\mathrm{He}$-${}_{}{}^4{}_{}{}^{}\mathrm{He}$ mixtures into the miscibility gap. The two types of dispersions, namely, superfluid droplets within a normal-fluid continuous phase and the inverse, evolve differently. Under certain conditions near the tricritical point, light scattering during the early stages of separation displays a halo at a time-dependent wave vector $k_m\propto t^{-\varphi }$, where $\varphi$ shows a crossover from slow ($\varphi \approx \frac{1}{3}$) to fast ($\varphi =1\mathrm{}$) growth within 0.1 s.