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Entanglement of Pure Two-Mode Gaussian States

R. W. Rendell·A. K. Rajagopal
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Abstract

The entanglement of general pure Gaussian two-mode states is examined in terms of the coefficients of the quadrature components of the wavefunction. The entanglement criterion and the entanglement of formation are directly evaluated as a function of these coefficients, without the need for deriving local unitary transformations. These reproduce the results of other methods for the special case of symmetric pure states which employ a relation between squeezed states and Einstein-Podolsky-Rosen correlations. The modification of the quadrature coefficients and the corresponding entanglement due to application of various optical elements is also derived.

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R. W. Rendell, A. K. Rajagopal. 2005-02-09. Entanglement of Pure Two-Mode Gaussian States. https://doi.org/10.1103/physreva.72.012330

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