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arXiv · 1705.05609

Deterministic phase measurements exhibiting super-sensitivity and super-resolution

Clemens Schäfermeier·Miroslav Ježek·Lars S. Madsen·Tobias Gehring·Ulrik L. Andersen
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Abstract

Phase super-sensitivity is obtained when the sensitivity in a phase measurement goes beyond the quantum shot noise limit, whereas super-resolution is obtained when the interference fringes in an interferometer are narrower than half the input wavelength. Here we show experimentally that these two features can be simultaneously achieved using a relatively simple setup based on Gaussian states and homodyne measurement. Using 430 photons shared between a coherent- and a squeezed vacuum state, we demonstrate a 22-fold improvement in the phase resolution while we observe a 1.7-fold improvement in the sensitivity. In contrast to previous demonstrations of super-resolution and super-sensitivity, this approach is fully deterministic.

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Clemens Schäfermeier, Miroslav Ježek, Lars S. Madsen, Tobias Gehring, Ulrik L. Andersen. 2018-01-25. Deterministic phase measurements exhibiting super-sensitivity and super-resolution. https://doi.org/10.1364/optica.5.000060

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