Quantum Information Put into Practice

Aleksandar Stojanović

Abstract: This publication put the accent on strategical problems in information transmission. The analysis is based on substantially different structure between classical (bit) and quantum information unit (qubit). The scientific methodology used in this publication is relatively new (single qubit transfer based on no-cloning theorem). Important part of publication is devoted to solving problems where quantum information processing offers much more prolific solutions than classical information processing. From practical point of view, the advances of quantum based information technologies have been presented.

S. Ya. Kilin

Daniel F. Walls, Gerard J Milburn

David G. Cory, Timothy F. Havel

Quantum entanglement, in which the physical properties of particles become correlated, is an essential property of quantum information systems. In their Perspective, [Cory and Havel][1] discuss results reported in the same issue by [ Roos et al .][2] and by [ Leibfried et al .][3] in which trapped ions were put into entangled quantum states. The two complementary studies show that substantial progress is being made in quantum information processing and point to practical applications of entangled states. [1]: http://www.sciencemag.org/cgi/content/full/304/5676/1456 [2]: http://www.sciencemag.org/cgi/content/short/304/5676/1478 [3]: http://www.sciencemag.org/cgi/content/short/304/5676/1476

Valerio Scarani, Helle Bechmann-Pasquinucci, Nicolas J. Cerf +3 more

Quantum key distribution (QKD) is the first quantum information task to reach the level of mature technology, already fit for commercialization. It aims at the creation of a secret key between authorized partners connected by a quantum channel and a classical authenticated channel. The security of the key can in principle be guaranteed without putting any restriction on an eavesdropper's power. This article provides a concise up-to-date review of QKD, biased toward the practical side. Essential theoretical tools that have been developed to assess the security of the main experimental platforms are presented (discrete-variable, continuous-variable, and distributed-phase-reference protocols).