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arXiv · 1511.01723

Unbalanced Homodyne Correlation Measurements

B. Kühn·W. Vogel
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Abstract

A method is introduced which allows to measure normal-ordered moments of the displaced photon-number operator up to high orders. It is based on unbalanced homodyne correlation measurements, the local oscillator being replaced by a displaced dephased laser. The measured moments yield a simple approximation of the full quantum state, which is obtained without the need of photon-number resolution. Quantum properties of light are efficiently certified through the direct detection of normal-ordered observables, which is illustrated for a weakly squeezed vacuum and a single-photon-added thermal state.

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B. Kühn, W. Vogel. 2016-04-20. Unbalanced Homodyne Correlation Measurements. https://doi.org/10.1103/physrevlett.116.163603

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