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arXiv · 2010.13910

Collision models can efficiently simulate any multipartite Markovian quantum dynamics

Marco Cattaneo·Gabriele De Chiara·Sabrina Maniscalco·Roberta Zambrini·Gian Luca Giorgi
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Abstract

We introduce the multipartite collision model, defined in terms of elementary interactions between subsystems and ancillae, and show that it can simulate the Markovian dynamics of any multipartite open quantum system. We develop a method to estimate an analytical error bound for any repeated interactions model, and we use it to prove that the error of our scheme displays an optimal scaling. Finally, we provide a simple decomposition of the multipartite collision model into elementary quantum gates, and show that it is efficiently simulable on a quantum computer according to the dissipative quantum Church-Turing theorem, i.e. it requires a polynomial number of resources.

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Marco Cattaneo, Gabriele De Chiara, Sabrina Maniscalco, Roberta Zambrini, Gian Luca Giorgi. 2021-04-04. Collision models can efficiently simulate any multipartite Markovian quantum dynamics. https://doi.org/10.1103/physrevlett.126.130403

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