Quality factor of a superfluid ³He weak link resonator

We measure the quality factor, Q for an oscillating membrane, which is in parallel with a superfluid ³He weak link array. We have constructed an effective cell model to help explain these results and find reasonable agreement between the experimental data and our theoretical model. The familiar effects of first and second viscosity have been considered as well as a new intrinsic dissipation that acts as a linear shunt conductance G across the weak link. Although the viscous terms dominate, as seen in single orifice weak links [1], the "shorting" effects of the shunt conductance noticably suppress the quality factor, especially at low temperatures.