| Full text | |
| Author(s): |
Mendonca, Paulo E. M. F.
[1]
;
Napolitano, Reginaldo D. J.
[2]
;
Marchiolli, Marcelo A.
[3]
;
Foster, Christopher J.
[1]
;
Liang, Yeong-Cherng
[4]
Total Authors: 5
|
| Affiliation: | [1] Univ Queensland, Dept Phys, Brisbane, Qld 4072 - Australia
[2] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil
[3] Univ Estadual Paulista, Inst Fis Teor, BR-01405900 Sao Paulo - Brazil
[4] Univ Sydney, Sch Phys, Sydney, NSW 2006 - Australia
Total Affiliations: 4
|
| Document type: | Journal article |
| Source: | Physical Review A; v. 78, n. 5, p. 052330, 2008. |
| Web of Science Citations: | 46 |
| Abstract | |
We propose an alternative fidelity measure (namely, a measure of the degree of similarity) between quantum states and benchmark it against a number of properties of the standard Uhlmann-Jozsa fidelity. This measure is a simple function of the linear entropy and the Hilbert-Schmidt inner product between the given states and is thus, in comparison, not as computationally demanding. It also features several remarkable properties such as being jointly concave and satisfying all of Jozsa's axioms. The trade-off, however, is that it is supermultiplicative and does not behave monotonically under quantum operations. In addition, metrics for the space of density matrices are identified and the joint concavity of the Uhlmann-Jozsa fidelity for qubit states is established. (AU) | |