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arXiv · 2405.09466

A geometric formulation to measure global and genuine entanglement in three-qubit systems

Salvio Luna-Hernandez·Marco Enriquez·Oscar Rosas-Ortiz
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Abstract

We introduce a purely geometric formulation for two different measures addressed to quantify the entanglement between different parts of a tripartite qubit system. Our approach considers the entanglement-polytope defined by the smallest eigenvalues of the reduced density matrices of the qubit-components. The measures identify global and genuine entanglement, and are respectively associated with the projection and rejection of a given point of the polytope on the corresponding biseparable segments. Solving the so called `inverse problem', we also discuss a way to force the system to behave in a particular form, which opens the possibility of controlling and manipulating entanglement for practical purposes.

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Salvio Luna-Hernandez, Marco Enriquez, Oscar Rosas-Ortiz. 2024-05-15. A geometric formulation to measure global and genuine entanglement in three-qubit systems. https://doi.org/10.1038/s41598-024-76566-9

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