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Strong subadditivity inequality for quantum entropies and four-particle entanglement

Asoka Biswas·G. S. Agarwal
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Abstract

Strong subadditivity inequality for a three-particle composite system is an important inequality in quantum information theory which can be studied via a four-particle entangled state. We use two three-level atoms in $Λ$ configuration interacting with a two-mode cavity and the Raman adiabatic passage technique for the production of the four-particle entangled state. Using this four-particle entanglement, we study for the first time various aspects of the strong subadditivity inequality.

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Asoka Biswas, G. S. Agarwal. 2003-07-29. Strong subadditivity inequality for quantum entropies and four-particle entanglement. https://doi.org/10.1103/physreva.68.054303

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