Mechanical frequency control in inductively coupled electromechanical systems

Nano-electromechanical systems couple mechanical motion to superconducting quantum circuits at microwave frequencies. While traditional, capacitive coupling strategies operate in the weak coupling regime, inductive coupling schemes based on partially suspended superconducting interference devices (SQUID) have demonstrated significantly improved coupling rates. Such systems are expected to allow for the exploration of phenomena beyond the linearized opto-mechanical interaction. Here, we present an investigation into the tuning of the mechanical resonance frequency in an inductively coupled system. The experimental data quantitatively corroborates theoretical predictions for SQUID-based electromechanical systems. In addition, we observe a magnetic field dependent tuning of the mechanical resonance frequency, which we attribute to an effective interaction of the atomic lattice and the superconducting vortex lattice.