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Improving quantum interferometry by using entanglement (to take a decision you'd better use entanglement)

G. M. D'Ariano·Matteo G. A Paris·Paolo Perinotti
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Abstract

We address the use of entanglement to improve the precision of generalized quantum interferometry, i.e. of binary measurements aimed to determine whether or not a perturbation has been applied by a given device. For the most relevant operations in quantum optics, we evaluate the optimal detection strategy and the ultimate bounds to the minimum detectable perturbation. Our results indicate that entanglement-assisted strategies improve the discrimination in comparison with conventional schemes. A concrete setup to approach performances of the optimal strategies is also suggested.

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G. M. D'Ariano, Matteo G. A Paris, Paolo Perinotti. 2001-10-17. Improving quantum interferometry by using entanglement (to take a decision you'd better use entanglement). https://doi.org/10.1103/physreva.65.062106

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