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Cited by 834

The DOI matches its Crossref record; 36 of the 36 references it cites were found in a registry or an index.

Quantum discord for two-qubitXstates

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Ali, Mazhar, Rau, A. R. P., Alber, G.·2010·Physical Review A
DOI 10.1103/physreva.81.042105
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Abstract

Quantum discord, a kind of quantum correlation, is defined as the difference between quantum mutual information and classical correlation in a bipartite system. In general, this correlation is different from entanglement, and quantum discord may be nonzero even for certain separable states. Even in the simple case of bipartite quantum systems, this different kind of quantum correlation has interesting and significant applications in quantum information processing. So far, quantum discord has been calculated explicitly only for a rather limited set of two-qubit quantum states and expressions for more general quantum states are not known. In this article, we derive explicit expressions for quantum discord for a larger class of two-qubit states, namely, a seven-parameter family of so called $X$ states that have been of interest in a variety of contexts in the field. We also study the relation between quantum discord, classical correlation, and entanglement for a number of two-qubit states to demonstrate that they are independent measures of correlation with no simple relative ordering between them.

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Metadata

Authors
Ali, M., Rau, A. R. P., & Alber, G.
Venue
Physical Review A
Publisher
American Physical Society (APS)
Published
2010-04-12
Volume
81
Issue
4
ISSN
  • 0556-2791 (ISSN-L)
  • 1050-2947
  • 1094-1622
DOI
10.1103/physreva.81.042105
OpenAlex
W2073595591
Cited by
834
References
36
FWCI
103.05
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Quantum discord for two-qubitXstates. https://app.cochat.ai/papers/10.1103/physreva.81.042105
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Ali, M., Rau, A. R. P., & Alber, G. (2010). Quantum discord for two-qubitXstates. Physical Review A. https://doi.org/10.1103/physreva.81.042105

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