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Generation of long-living entanglement between two separate atoms

Özgür Çakir·Ho Trung Dung·Ludwig Knöll·Dirk-Gunnar Welsch
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Abstract

A scheme for non-conditional generation of long-living maximally entangled states between two spatially well separated atoms is proposed. In the scheme, $\Lambda$-type atoms pass a resonator-like equipment of dispersing and absorbing macroscopic bodies giving rise to body-assisted electromagnetic field resonances of well-defined heights and widths. Strong atom-field coupling is combined with weak atom-field coupling to realize entanglement transfer from the dipole-allowed transitions to the dipole-forbidden transitions, thereby the entanglement being preserved when the atoms depart from the bodies and from each other. The theory is applied to the case of the atoms passing by a microsphere.

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Özgür Çakir, Ho Trung Dung, Ludwig Knöll, Dirk-Gunnar Welsch. 2004-10-05. Generation of long-living entanglement between two separate atoms. https://doi.org/10.1103/physreva.71.032326

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