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arXiv · 1612.08208

Scalable quantum circuit and control for a superconducting surface code

R. Versluis·S. Poletto·N. Khammassi·N. Haider·D. J. Michalak·A. Bruno·K. Bertels·L. DiCarlo
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Abstract

We present a scalable scheme for executing the error-correction cycle of a monolithic surface-code fabric composed of fast-flux-tuneable transmon qubits with nearest-neighbor coupling. An eight-qubit unit cell forms the basis for repeating both the quantum hardware and coherent control, enabling spatial multiplexing. This control uses three fixed frequencies for all single-qubit gates and a unique frequency detuning pattern for each qubit in the cell. By pipelining the interaction and readout steps of ancilla-based $X$- and $Z$-type stabilizer measurements, we can engineer detuning patterns that avoid all second-order transmon-transmon interactions except those exploited in controlled-phase gates, regardless of fabric size. Our scheme is applicable to defect-based and planar logical qubits, including lattice surgery.

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R. Versluis, S. Poletto, N. Khammassi, N. Haider, D. J. Michalak, A. Bruno, K. Bertels, L. DiCarlo. 2016-12-24. Scalable quantum circuit and control for a superconducting surface code. https://doi.org/10.1103/physrevapplied.8.034021

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