Transition from synchronous to asynchronous superfluid phase slippage in an aperture array

Abstract

We have investigated the dynamics of superfluid phase slippage in an array of apertures. The magnitude of the dissipative phase slips shows that they occur simultaneously in all the apertures when the temperature is near ${T}_{\ensuremath{\lambda}}\ensuremath{-}T\ensuremath{\approx}10\phantom{\rule{0.3em}{0ex}}\mathrm{mK}$ and subsequently lose their simultaneity as the temperature is lowered. We describe three experiments to probe the mechanisms underlying the synchronous behavior. The results raise fundamental questions about the dynamics of phase slippage in a multiply connected geometry.