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arXiv · 1010.2848

Completely mixed state is a critical point for three-qubit entanglement

Sayatnova Tamaryan
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Abstract

Pure three-qubit states have five algebraically independent and one algebraically dependent polynomial invariants under local unitary transformations and an arbitrary entanglement measure is a function of these six invariants. It is shown that if the reduced density operator of a some qubit is a multiple of the unit operator, than the geometric entanglement measure of the pure three-qubit state is absolutely independent of the polynomial invariants and is a constant for such tripartite states. Hence a one-particle completely mixed state is a critical point for the geometric measure of entanglement.

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BibTeXRIS

Sayatnova Tamaryan. 2010-10-14. Completely mixed state is a critical point for three-qubit entanglement. https://doi.org/10.1016/j.physleta.2011.04.056

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