dorsal/arxiv
View SchemaOrdering two-qubit states with concurrence and negativity
| Authors | Adam Miranowicz, Andrzej Grudka |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0404053 |
| URL | https://arxiv.org/abs/quant-ph/0404053 |
| DOI | 10.1103/PhysRevA.70.032326 |
| Journal | Phys. Rev. A 70, 032326 (2004) |
Abstract
We study the ordering of two-qubit states with respect to the degree of bipartite entanglement using the Wootters concurrence -- a measure of the entanglement of formation, and the negativity -- a measure of the entanglement cost under the positive-partial-transpose-preserving operations. For two-qubit pure states, the negativity is the same as the concurrence. However, we demonstrate analytically on simple examples of various mixtures of Bell and separable states that the entanglement measures can impose different orderings on the states. We show which states, in general, give the maximally different predictions, (i) when one of the states has the concurrence greater but the negativity smaller than those for the other state, and (ii) when the states are entangled to the same degree according to one of the measures, but differently according to the other.
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"abstract": "We study the ordering of two-qubit states with respect to the degree of\nbipartite entanglement using the Wootters concurrence -- a measure of the\nentanglement of formation, and the negativity -- a measure of the entanglement\ncost under the positive-partial-transpose-preserving operations. For two-qubit\npure states, the negativity is the same as the concurrence. However, we\ndemonstrate analytically on simple examples of various mixtures of Bell and\nseparable states that the entanglement measures can impose different orderings\non the states. We show which states, in general, give the maximally different\npredictions, (i) when one of the states has the concurrence greater but the\nnegativity smaller than those for the other state, and (ii) when the states are\nentangled to the same degree according to one of the measures, but differently\naccording to the other.",
"arxiv_id": "quant-ph/0404053",
"authors": [
"Adam Miranowicz",
"Andrzej Grudka"
],
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"quant-ph"
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"doi": "10.1103/PhysRevA.70.032326",
"journal_ref": "Phys. Rev. A 70, 032326 (2004)",
"title": "Ordering two-qubit states with concurrence and negativity",
"url": "https://arxiv.org/abs/quant-ph/0404053"
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