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arXiv · 0801.3831

Experimental Quantum Process Discrimination

Anthony Laing·Terry Rudolph·Jeremy L. O'Brien
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Abstract

Discrimination between unknown processes chosen from a finite set is experimentally shown to be possible even in the case of non-orthogonal processes. We demonstrate unambiguous deterministic quantum process discrimination (QPD) of non-orthogonal processes using properties of entanglement, additional known unitaries, or higher dimensional systems. Single qubit measurement and unitary processes and multipartite unitaries (where the unitary acts non-separably across two distant locations) acting on photons are discriminated with a confidence of $\geq97%$ in all cases.

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Anthony Laing, Terry Rudolph, Jeremy L. O'Brien. 2008-07-01. Experimental Quantum Process Discrimination. https://doi.org/10.1103/physrevlett.102.160502

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