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arXiv · 2010.14363

Classical simulation of Gaussian quantum circuits with non-Gaussian input states

Ulysse Chabaud·Giulia Ferrini·Frédéric Grosshans·Damian Markham
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Abstract

We consider Gaussian quantum circuits supplemented with non-Gaussian input states and derive sufficient conditions for efficient classical strong simulation of these circuits. In particular, we generalise the stellar representation of continuous-variable quantum states to the multimode setting and relate the stellar rank of the input non-Gaussian states, a recently introduced measure of non-Gaussianity, to the cost of evaluating classically the output probability densities of these circuits. Our results have consequences for the strong simulability of a large class of near-term continuous-variable quantum circuits.

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Ulysse Chabaud, Giulia Ferrini, Frédéric Grosshans, Damian Markham. 2020-10-27. Classical simulation of Gaussian quantum circuits with non-Gaussian input states. https://doi.org/10.1103/physrevresearch.3.033018

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