Milne, A, Jennings, D orcid.org/0000-0003-1201-3725 and Rudolph, T (2015) Geometric representation of two-qubit entanglement witnesses. Physical Review A, 92 (1). 012311. ISSN 2469-9926
Abstract
Any two-qubit state can be represented geometrically by a steering ellipsoid inside the Bloch sphere. We extend this approach to represent any block-positive two-qubit operator B. We derive a classification scheme based on the positivity of det B and det BTB; this shows that any ellipsoid inside the Bloch sphere must represent either a two-qubit state or a two-qubit entanglement witness. We focus on such witnesses and their corresponding ellipsoids, finding that properties such as witness optimality are naturally manifest in this geometric representation.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015 American Physical Society. Reproduced in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Theoretical Physics (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 06 Dec 2018 09:21 |
Last Modified: | 06 Dec 2018 09:21 |
Status: | Published |
Publisher: | American Physical Society |
Identification Number: | 10.1103/PhysRevA.92.012311 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:139395 |