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Mode-Wise Entanglement of Gaussian States

Alonso Botero·Benni Reznik
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Abstract

We address the decomposition of a multi-mode pure Gaussian state with respect to a bi-partite division of the modes. For any such division the state can always be expressed as a product state involving entangled two-mode squeezed states and single mode local states at each side. The character of entanglement of the state can therefore be understood modewise; that is, a given mode on one side is entangled with only one corresponding mode of the other, and therefore the total bi-partite entanglement is the sum of the modewise entanglement. This decomposition is generally not applicable to all mixed Gaussian states. However, the result can be extended to a special family of "isotropic" states, characterized by a phase space covariance matrix with a completely degenerate symplectic spectrum.

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Alonso Botero, Benni Reznik. 2003-01-16. Mode-Wise Entanglement of Gaussian States. https://doi.org/10.1103/physreva.67.052311

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