Phys. Rev. A 63, 054104 (2001) [4 pages]Maximum-likelihood reconstruction of completely positive mapsReceived 15 September 2000; published 13 April 2001 We present a method for the determination of the completely positive (CP) map describing a physical device based on random preparation of the input states, random measurements at the output, and the maximum-likelihood principle. In the numerical implementation the constraint of completely positivity can be imposed by exploiting the isomorphism between linear transformations from Hilbert spaces H to K and linear operators in K⊗H. The effectiveness of the method is shown on the basis of some examples of reconstruction of CP maps related to quantum communication channels for qubits. © 2001 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevA.63.054104
DOI:
10.1103/PhysRevA.63.054104
PACS:
03.65.-w, 03.67.Hk
|
|
About | Terms and Conditions | Subscriptions | Search | Help
Use of the American Physical Society websites and journals implies that the user has read and agrees to our Terms and Conditions and any applicable Subscription Agreement. Physical Review®, Physical Review Letters®, Reviews of Modern Physics®, and Physical Review Special Topics® are trademarks of the American Physical Society.