Effects of³He impurities on the⁴He solid-liquid interface

Abstract

Using crystallization waves we have measured the interfacial stiffness,$\bar \alpha$, and the temperature dependence of the growth resistance, (Km)⁻¹, of the⁴He solid-liquid interface in the presence of³He impurities. For the purest⁴He sample, (Km)⁻¹ is consistent at the lowest temperatures with the assumption that the growth velocity is limited by the scattering of ballistic phonons from the moving interface. At higher concentrations of³He, we observe that (Km)⁻¹ increases exponentially with temperature below 0.25 K. We observe that$\bar \alpha$ decreases with increasing³He concentration.