Condensation ofHe3Atoms onto Quantized Vortex Lines in Superfluid Helium

Abstract

We have measured the mobility of positive and negative ions trapped on vortex lines in ${\mathrm{He}}^3$-${\mathrm{He}}^4$ solutions at temperatures from 0.3 to 1.6 K. Abrupt changes in the mobility at certain critical temperatures are interpreted as being associated with the condensation of ${\mathrm{He}}^3$ atoms onto the vortex cores. The dependence of the critical temperature on the bulk ${\mathrm{He}}^3$ concentration is found to be in good agreement with a simple condensation theory.