Équipe de Recherche en Physique de l'Information Quantique


Author = {R. Blume-Kohout and H.K. Ng and D. Poulin and L. Viola},
Date-Added = {2010-03-16 13:15:33 -0400},
Date-Modified = {2010-12-09 14:07:09 -0500},
Eprint = {arXiv:1006.1358},
Journal = {Phys. Rev. A},
Pages = {062306},
Title = {Information preserving structures: a general framework for quantum zero-error information},
Volume = {82},
Year = {2010},
Local-Url = {BNPV10b1.pdf},
Abstract = {Quantum systems carry information. Quantum theory supports at least two distinct kinds of
information (classical and quantum), and a variety of different ways to encode and preserve information
in physical systems. A system's ability to carry information is constrained and defined
by the noise in its dynamics. This paper introduces an operational framework, using informationpreserving
structures to classify all the kinds of information that can be perfectly (i.e., with zero
error) preserved by quantum dynamics. We prove that every perfectly preserved code has the same
structure as a matrix algebra, and that preserved information can always be corrected. We also
classify distinct operational criteria for preservation (e.g., ``noiseless'', ``unitarily correctible'', etc.)
and introduce two new and natural criteria for measurement-stabilized and unconditionally preserved
codes. Finally, for several of these operational critera, we present efficient [polynomial in the
state-space dimension] algorithms to find all of a channel's information-preserving structures.}}