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arXiv · 1702.02271

A tight Cramér-Rao bound for joint parameter estimation with a pure two-mode squeezed probe

Mark Bradshaw·Syed M Assad·Ping Koy Lam
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Abstract

We calculate the Holevo Cramér-Rao bound for estimation of the displacement experienced by one mode of an two-mode squeezed vacuum state with squeezing r and find that it is equal to 4exp(-2r). This equals the sum of the mean squared error obtained from a dual homodyne measurement, indicating that the bound is tight and that the dual homodyne measurement is optimal.

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Mark Bradshaw, Syed M Assad, Ping Koy Lam. 2019-01-15. A tight Cramér-Rao bound for joint parameter estimation with a pure two-mode squeezed probe. https://doi.org/10.1016/j.physleta.2017.06.024

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