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Building Gaussian Cluster States by Linear Optics

Peter van Loock·Christian Weedbrook·Mile Gu
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Abstract

The linear optical creation of Gaussian cluster states, a potential resource for universal quantum computation, is investigated. We show that for any Gaussian cluster state, the canonical generation scheme in terms of QND-type interactions, can be entirely replaced by off-line squeezers and beam splitters. Moreover, we find that, in terms of squeezing resources, the canonical states are rather wasteful and we propose a systematic way to create cheaper states. As an application, we consider Gaussian cluster computation in multiple-rail encoding. This encoding may reduce errors due to finite squeezing, even when the extra rails are achieved through off-line squeezing and linear optics.

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Peter van Loock, Christian Weedbrook, Mile Gu. 2006-10-15. Building Gaussian Cluster States by Linear Optics. https://doi.org/10.1103/physreva.76.032321

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