Achieving high-performance quantum computing with superconducting qubits requires a good understanding of the various loss mechanisms that can degrade qubit performance. One such potential loss mechanism is undesired electromechanical coupling mediated by piezoelectric effects. It can occur even in centrosymmetric materials due to interface symmetry breaking. In our recent cryogenic microwave transmission measurements, we observed such interface piezoelectricity at the aluminum-silicon and aluminum-sapphire heterostructures, a widely used material combination in superconducting qubit fabrication. This phenomenon may contribute to significant decoherence in superconducting qubits. In this project, we aim to experimentally investigate the impact of interface piezoelectricity-induced decoherence in superconducting qubits. We will fabricate qubit capacitors with an interdigitated geometry, allowing them to function as both shunt capacitors and piezoelectric transducers. By tuning the qubit frequency to match the electromechanical resonance frequency of the transducer, we will be able to perform qubit state manipulation via surface acoustic waves. Additionally, we will examine how electromechanical resonance influences qubit relaxation times. This study will provide critical insights for improving the performance of future superconducting qubits.
Project is currently funded by: Federal