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arXiv · 1710.04387

A local and scalable lattice renormalization method for ballistic quantum computation

Daniel Herr·Alexandru Paler·Simon J. Devitt·Franco Nori
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Abstract

A recent proposal has shown that it is possible to perform linear-optics quantum computation using a ballistic generation of the lattice. Yet, due to the probabilistic generation of its cluster state, it is not possible to use the fault-tolerant Raussendorf lattice, which requires a lower failure rate during the entanglement-generation process. Previous work in this area showed proof-of-principle linear-optics quantum computation, while this paper presents an approach to it which is more practical, satisfying several key constraints. We develop a classical measurement scheme, that purifies a large faulty lattice to a smaller lattice with entanglement faults below threshold. A single application of this method can reduce the entanglement error rate to $7\%$ for an input failure rate of $25\%$. Thus, we can show that it is possible to achieve fault tolerance for ballistic methods.

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Daniel Herr, Alexandru Paler, Simon J. Devitt, Franco Nori. 2017-10-12. A local and scalable lattice renormalization method for ballistic quantum computation. https://doi.org/10.1038/s41534-018-0076-0

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