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arXiv · 1501.02878

Heisenberg-limited metrology with a squeezed vacuum state, three-mode mixing, and information recycling

Behnam Tonekaboni·Simon A. Haine·Stuart S. Szigeti
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Abstract

We have previously shown that quantum-enhanced atom interferometry can be achieved by mapping the quantum state of squeezed optical vacuum to one of the atomic inputs via a beamsplitter-like process [Phys.~Rev.~A \textbf{90}, 063630 (2014)]. Here we ask the question: is a better phase sensitivity possible if the quantum state transfer (QST) is described by a three-mode-mixing model, rather than a beamsplitter? The answer is yes, but only if the portion of the optical state not transferred to the atoms is incorporated via information recycling. Surprisingly, our scheme gives a better sensitivity for lower QST efficiencies and with a sufficiently large degree of squeezing can attain near-Heisenberg-limited sensitivities for arbitrarily small QST efficiencies. Furthermore, we use the quantum Fisher information to demonstrate the near optimality of our scheme.

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Behnam Tonekaboni, Simon A. Haine, Stuart S. Szigeti. 2015-03-12. Heisenberg-limited metrology with a squeezed vacuum state, three-mode mixing, and information recycling. https://doi.org/10.1103/physreva.91.033616

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