Superconducting quantum circuits are one of the leading technologies for building quantum computers. These circuits are made of superconducting resonators with quality factors on the order of $10^5-10^6$. Because of the high device Q-factor when operating in the superconducting regime, loss mechanisms that would otherwise be insignificant to the overall resonator Q-factor start to become important. One such mechanism we explore in this project is the impact of surface piezoelectricity on qubit and resonator quality factors. Surface piezoelectricity arises due to atomic dipoles at material interfaces with broken symmetry. We investigate the effect of this loss channel on resonators incorporating parallel-plate and lateral capacitors and show how the energy dissipation could potentially be suppressed by fabricating the LC resonators on an acoustic bandgap crystal. This study shows the need for co-designing acoustics and electrical circuits in superconducting quantum computers.
Project ended 08/24/2022.