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arXiv · 1804.09444

Tailoring Non-Gaussian Continuous-Variable Graph States

Mattia Walschaers·Supratik Sarkar·Valentina Parigi·Nicolas Treps
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Abstract

Graph states are the backbone of measurement-based continuous-variable quantum computation. However, experimental realisations of these states induce Gaussian measurement statistics for the field quadratures, which poses a barrier to obtain a genuine quantum advantage. In this letter, we propose mode-selective photon addition and subtraction as viable and experimentally feasible pathways to introduce non-Gaussian features in such continuous-variable graph states. In particular, we investigate how the non-Gaussian properties spread among the vertices of the graph, which allows us to show the degree of control that is achievable in this approach.

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Mattia Walschaers, Supratik Sarkar, Valentina Parigi, Nicolas Treps. 2018-11-29. Tailoring Non-Gaussian Continuous-Variable Graph States. https://doi.org/10.1103/physrevlett.121.220501

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