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arXiv · 1903.02162

Robust fault tolerance for continuous-variable cluster states with excess anti-squeezing

Blayney W. Walshe·Lucas J. Mensen·Ben Q. Baragiola·Nicolas C. Menicucci
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Abstract

The immense scalability of continuous-variable cluster states motivates their study as a platform for quantum computing, with fault tolerance possible given sufficient squeezing and appropriately encoded qubits [Menicucci, PRL 112, 120504 (2014)]. Here, we expand the scope of that result by showing that additional anti-squeezing has no effect on the fault-tolerance threshold, removing the purity requirement for experimental continuous-variable cluster-state quantum computing. We emphasize that the appropriate experimental target for fault-tolerant applications is to directly measure 15-17 dB of squeezing in the cluster state rather than the more conservative upper bound of 20.5 dB.

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Blayney W. Walshe, Lucas J. Mensen, Ben Q. Baragiola, Nicolas C. Menicucci. 2019-03-06. Robust fault tolerance for continuous-variable cluster states with excess anti-squeezing. https://doi.org/10.1103/physreva.100.010301

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