Please use this identifier to cite or link to this item:
Title: Wigner tomography of two-qubit states and quantum cryptography
Authors: Durt, T.
Kurtsiefer, C. 
Lamas-Linares, A. 
Ling, A. 
Issue Date: 31-Oct-2008
Citation: Durt, T., Kurtsiefer, C., Lamas-Linares, A., Ling, A. (2008-10-31). Wigner tomography of two-qubit states and quantum cryptography. Physical Review A - Atomic, Molecular, and Optical Physics 78 (4) : -. ScholarBank@NUS Repository.
Abstract: Tomography of the two-qubit density matrix shared by Alice and Bob is an essential ingredient for guaranteeing an acceptable margin of confidentiality during the establishment of a secure fresh key through the quantum key distribution scheme. We show how the Singapore protocol for key distribution is optimal from this point of view, due to the fact that it is based on so-called symmetric informationally complete positive-operator-valued measure (SIC POVM) qubit tomography which allows the most accurate full tomographic reconstruction of an unknown density matrix on the basis of a restricted set of experimental data. We illustrate with the help of experimental data the deep connections that exist between SIC POVM tomography and discrete Wigner representations. We also emphasize the special role played by Bell states in this approach and propose a protocol for quantum key distribution during which a third party is able to concede or to deny a posteriori to the authorized users the ability to build a fresh cryptographic key. © 2008 The American Physical Society.
Source Title: Physical Review A - Atomic, Molecular, and Optical Physics
ISSN: 10502947
DOI: 10.1103/PhysRevA.78.042338
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.