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arXiv · 1311.3538

Noise analysis of single-qumode Gaussian operations using continuous-variable cluster states

Rafael N. Alexander·Seiji C. Armstrong·Ryuji Ukai·Nicolas C. Menicucci
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Abstract

We consider measurement-based quantum computation that uses scalable continuous-variable cluster states with a one-dimensional topology. The physical resource, known here as the dual-rail quantum wire, can be generated using temporally multiplexed offline squeezing and linear optics or by using a single optical parametric oscillator. We focus on an important class of quantum gates, specifically Gaussian unitaries that act on single modes, which gives universal quantum computation when supplemented with multi-mode operations and photon-counting measurements. The dual-rail wire supports two routes for applying single-qumode Gaussian unitaries: the first is to use traditional one-dimensional quantum-wire cluster-state measurement protocols. The second takes advantage of the dual-rail quantum wire in order to apply unitaries by measuring pairs of qumodes called macronodes. We analyze and compare these methods in terms of the suitability for implementing single-qumode Gaussian measurement-based quantum computation.

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Rafael N. Alexander, Seiji C. Armstrong, Ryuji Ukai, Nicolas C. Menicucci. 2014-10-13. Noise analysis of single-qumode Gaussian operations using continuous-variable cluster states. https://doi.org/10.1103/physreva.90.062324

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