Different state orderings by two entanglement measures: Concurrence vs negativity predictions
Year: 2004
Type: preprint
Abstract: We study the ordering of two-qubit states with respect to the degree of 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 on simple examples of various mixtures of Bell and separable states that the entanglement measures can give different orderings if at least one of the states is mixed. We show analytically which states 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.
Source: arXiv (Cornell University)
Authors: Adam Miranowicz, Andrzej Grudka
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2567654975