arXiv:1209.2748 · European Journal of Physics

Pedagogical introduction to the entropy of entanglement for Gaussian states

Tommaso F. Demarie

Published Mar 28, 2018• 26 citations

Abstract

Abstract In quantum information theory, the entropy of entanglement is a standard measure of bipartite entanglement between two partitions of a composite system. For a particular class of continuous variable quantum states, the Gaussian states, the entropy of entanglement can be expressed elegantly in terms of symplectic eigenvalues , elements that characterise a Gaussian state and depend on the correlations of the canonical variables. We give a rigorous step-by-step derivation of this result and provide physical insights, together with an example that can be useful in practice for calculations.

DOI: 10.1088/1361-6404/aaaad0

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