Flux Tunable Superconductings Qubits With 3D Wiring

Superconducting qubits have the potential to lead to large-scale quantum computers, where 10^5 or more qubits are arranged in two-dimensional arrays forming quantum processing units (QPUs) on silicon chips. Operating such an array necessarily requires control signals to come from wires in the third dimension, so as to avoid overlapping control lines on the device itself. While various implementations of 3D wiring have been realized in the last few years, none has been used with flux-tunable superconducting qubits, which require a current line to inductively bias the superconducting loop of a SQUID. In this talk, we show and characterize the performance of tunable superconducting Xmon transmon qubits using the quantum socket, for which the control wiring is fully 3D, including the fast flux bias lines used for frequency tuning. We demonstrate one-qubit gates and perform quantum gate tomography to quantify gate fidelity as a function of flux bias for two Xmon transmon qubits.