Damping of a Micro-electromechanical Resonator in the Presence of Quantum Turbulence Generated by a Quartz Tuning Fork

A micro-electromechanical resonator, consisting of a \(125 \times 125\,\upmu \hbox {m}^2\) center plate suspended \(2\,\upmu \hbox {m}\) above a substrate, was immersed in \(^4\)He along with a quartz tuning fork. The tuning fork was placed 5 mm above the resonator and was used to generate turbulence. The damping of the resonator was investigated in the presence of turbulence generated by the tuning fork. We observe a velocity, \(v_c \simeq 5\,\hbox {mm}\,\hbox {s}^{-1}\), above which the damping on the resonator is drastically reduced for all tuning fork velocities studied. We attribute this change in damping to the shedding and capture of vortices.