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arXiv · 1908.03117

Entanglement distance for an arbitrary state of M qubits

Denise Cocchiarella·Stefano Scali·Salvatore Ribisi·Bianca Nardi·Ghofrane Bel Hadj Aissa·Roberto Franzosi
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Abstract

We propose a measure of entanglement that can be computed for any pure state of an $M$-qubit system. The entanglement measure has the form of a distance that we derive from an adapted application of the Fubini-Study metric. This measure is invariant under local unitary transformations and defined as trace of a suitable metric that we derive, the entanglement metric $\tilde{g}$. Furthermore, the analysis of the eigenvalues of $\tilde{g}$ gives information about the robustness of entanglement.

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Denise Cocchiarella, Stefano Scali, Salvatore Ribisi, Bianca Nardi, Ghofrane Bel Hadj Aissa, Roberto Franzosi. 2019-08-08. Entanglement distance for an arbitrary state of M qubits. https://doi.org/10.1103/physreva.101.042129

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