Superconducting through-silicon vias as capacitive elements in quantum circuits*

Superconducting qubits and their control components typically require large capacitances.  The dimensions of the capacitors can be large due to the relatively low capacitance density of 2D planar designs.  In this talk, I will discuss our recent work utilizing high-quality superconducting through-silicon vias (TSVs) as the capacitive element in both qubits and readout resonators.  The introduction of TSVs has led to a reduction in the size of the qubits and resonators, while maintaining a high qubit coherence [1].  I will additionally describe our work exploring the use of TSVs as part of a hybrid superconducting-semiconducting qubit platforms [2]. 

[1] T. M. Hazard et al., Appl. Phys. Lett. 123, 154004 (2023). 

[2] T. M. Hazard et al., Phys. Rev. Appl. 20, 034056 (2023).