Collision models can efficiently simulate any multipartite Markovian quantum dynamics

TL;DR

This paper introduces a multipartite collision model that can efficiently simulate any multipartite Markovian quantum dynamics, providing error bounds and a quantum gate decomposition for efficient quantum computer implementation.

Contribution

The paper presents a new collision model for multipartite quantum systems, with analytical error bounds and a quantum gate decomposition for efficient simulation.

Findings

Error bounds scale optimally with interactions

Model can be efficiently simulated on quantum computers

Decomposition into elementary quantum gates is feasible

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.