Persistent Currents and Dissipation in theAandBPhases of LiquidHe3

Abstract

We report observations of long-lived persistent currents in both the $A$ and $B$ phases of ${}_{}{}^3{}_{}{}^{}\mathrm{He}$. In this work we have exploited the relation between the dissipation of small-amplitude oscillatory superflow and the average relative velocity between the superfluid and normal-fluid components. This provides a new technique for the nondestructive determination of the superfluid velocity associated with persistent currents in liquid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$.