arXiv:1703.05828 · Applied Physics Letters

Double-sided coaxial circuit QED with out-of-plane wiring

Joseph Rahamim, Tanja Behrle, M. J. Peterer, A. Patterson, P. A. Spring, T. Tsunoda, R. Manenti, Giovanna Tancredi, Peter Leek

Published May 29, 2017• 72 citations

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Abstract

Superconducting circuits are well established as a strong candidate platform for the development of quantum computing. In order to advance to a practically useful level, architectures are needed which combine arrays of many qubits with selective qubit control and readout, without compromising on coherence. Here, we present a coaxial circuit quantum electrodynamics architecture in which qubit and resonator are fabricated on opposing sides of a single chip, and control and readout wiring are provided by coaxial wiring running perpendicular to the chip plane. We present characterization measurements of a fabricated device in good agreement with simulated parameters and demonstrating energy relaxation and dephasing times of T1 = 4.1 μs and T2 = 5.7 μs, respectively. The architecture allows for scaling to large arrays of selectively controlled and measured qubits with the advantage of all wiring being out of the plane.

DOI: 10.1063/1.4984299

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