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arXiv · 1105.6310

Sub-Heisenberg estimation of non-random phase-shifts

Ángel Rivas·Alfredo Luis
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Abstract

We provide evidence that the uncertainty in detection of small and deterministic phase-shift deviations from a working point can be lower than the Heisenberg bound, for fixed finite mean number of photons. We achieve that by exploiting non-linearity of estimators and coherence with the vacuum.

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Ángel Rivas, Alfredo Luis. 2012-09-27. Sub-Heisenberg estimation of non-random phase-shifts. https://doi.org/10.1088/1367-2630%2F14%2F9%2F093052

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