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Lower bounds on the complexity of simulating quantum gates

Andrew M. Childs·Henry L. Haselgrove·Michael A. Nielsen
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Abstract

We give a simple proof of a formula for the minimal time required to simulate a two-qubit unitary operation using a fixed two-qubit Hamiltonian together with fast local unitaries. We also note that a related lower bound holds for arbitrary n-qubit gates.

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Andrew M. Childs, Henry L. Haselgrove, Michael A. Nielsen. 2003-07-25. Lower bounds on the complexity of simulating quantum gates. https://doi.org/10.1103/physreva.68.052311

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