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arXiv · 1206.1870

Exploring Macroscopic Entanglement with a Single Photon and Coherent States

Pavel Sekatski·Nicolas Sangouard·Magdalena Stobinska·Felix Bussieres·Mikael Afzelius·Nicolas Gisin
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Abstract

Entanglement between macroscopically populated states can easily be created by combining a single photon and a bright coherent state on a beam-splitter. Motivated by the simplicity of this technique, we report on a method using displacement operations in the phase space and basic photon detections to reveal such an entanglement. We demonstrate through preliminary experimental results, that this eminently feasible approach provides an attractive way for exploring entanglement at various scales, ranging from one to a thousand photons. This offers an instructive viewpoint to gain insight into the reasons that make it hard to observe quantum features in our macroscopic world.

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Pavel Sekatski, Nicolas Sangouard, Magdalena Stobinska, Felix Bussieres, Mikael Afzelius, Nicolas Gisin. 2012-06-08. Exploring Macroscopic Entanglement with a Single Photon and Coherent States. https://doi.org/10.1103/physreva.86.060301

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