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arXiv · 1210.5799

Surface code with decoherence: An analysis of three superconducting architectures

Joydip Ghosh·Austin G. Fowler·Michael R. Geller
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Abstract

We consider realistic, multi-parameter error models and investigate the performance of the surface code for three possible fault-tolerant superconducting quantum computer architectures. We map amplitude and phase damping to a diagonal Pauli "depolarization" channel via the Pauli twirl approximation, and obtain the logical error rate as a function of the qubit T1, T2 and state preparation, gate, and readout errors. A numerical Monte Carlo simulation is performed to obtain the logical error rates and a leading-order analytic formula is derived to estimate their behavior below threshold. Our results suggest that scalable fault-tolerant quantum computation should be possible with existing superconducting devices.

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Joydip Ghosh, Austin G. Fowler, Michael R. Geller. 2012-11-29. Surface code with decoherence: An analysis of three superconducting architectures. https://doi.org/10.1103/physreva.86.062318

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