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arXiv · 1210.1514

Creating and detecting micro-macro photon-number entanglement by amplifying and de-amplifying a single-photon entangled state

Roohollah Ghobadi·Alexander Lvovsky·Christoph Simon
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Abstract

We propose a scheme for the observation of micro-macro entanglement in photon number based on amplifying and de-amplifying a single-photon entangled state in combination with homodyne quantum state tomography. The created micro-macro entangled state, which exists between the amplification and de-amplification steps, is a superposition of two components with mean photon numbers that differ by approximately a factor of three. We show that for reasonable values of photon loss it should be possible to detect micro-macro photon-number entanglement where the macro system has a mean number of one hundred photons or more.

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Roohollah Ghobadi, Alexander Lvovsky, Christoph Simon. 2012-10-04. Creating and detecting micro-macro photon-number entanglement by amplifying and de-amplifying a single-photon entangled state. https://doi.org/10.1103/physrevlett.110.170406

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