"Quantum communication is based on the physical laws of quantum mechanics. This introduced a new concept to information science. Information theory is now no longer independent of the particular choice of the physical implementation. One result is the possibility of a fundamentally new mode of information transmission: uncon\u00ADditionally secure communication.\u00A0 Secure coherent optical communication systems based on homodyne detection are already practical in low loss channels using current quantum technology. To securely transmit information over large distances, almost lossless and noiseless optical communication between satellites can be exploited. But first, any ground station has to communicate with the satellites through free-space atmosphere exhibiting a wide variety of deleterious effects producing noise and errors in transmitted coherent and entangled quantum states. Such noisy channels can function only with efficiently operating error correction. In this project we want to develop quantum error correcting technologies for coherent quantum communication that will enable faithful transmission of quantum states of light over an atmospheric channel.\u00A0 The results have a direct application to coherent quantum communication, but they are also highly interesting from a general physics point of view."@en . " quantum communication" . "2010-06-30+02:00"^^ . "0"^^ . "http://www.isvav.cz/projectDetail.do?rowId=GC202/07/J040"^^ . . . . . "Solution project was on schedule in terms of both professional and innovative use of funds."@en . . . . . "quantum optics; quantum communication; squeezed light; quantum entanglement; homodyne detection"@en . "\u0158e\u0161en\u00ED projektu prob\u011Bhlo podle pl\u00E1nu jak z hlediska odborn\u00E9ho tak i z hlediska \u010Derp\u00E1n\u00ED finan\u010Dn\u00EDch prost\u0159edk\u016F."@cs . . "2010-04-16+02:00"^^ . . . "2015-02-09+01:00"^^ . . "Kvantov\u00E1 komunikace je zalo\u017Eena na fyzik\u00E1ln\u00EDch z\u00E1konech kvantov\u00E9 mechaniky. Ta poskytuje nov\u00FD koncept informa\u010Dn\u00ED teorie, kter\u00E1\u00A0ji\u017E nen\u00ED\u00A0nez\u00E1visl\u00E1 na dan\u00E9 fyzik\u00E1ln\u00ED implementaci. Jedn\u00EDm\u00A0z v\u00FDsledk\u016F je\u00A0fundament\u00E1ln\u011B nov\u00FD m\u00F3d p\u0159enosu informace: nepodm\u00EDn\u011Bn\u011B bezpe\u010Dn\u00E1 komunikace. Bezpe\u010Dn\u00E9 koherentn\u00ED komunika\u010Dn\u00ED syst\u00E9my zalo\u017Een\u00E9 na homodyn\u00ED detekci\u00A0jsou\u00A0realizovateln\u00E9 s n\u00EDzk\u00FDmi ztr\u00E1tami ji\u017E se sou\u010Dasnou kvantovou technologi\u00ED. Pro bezpe\u010Dn\u00FD p\u0159enos informace na velk\u00E9 vzd\u00E1lenosti m\u016F\u017Ee b\u00FDt vyu\u017Eita t\u00E9m\u011B\u0159 bezztr\u00E1tov\u00E1 a bez\u0161umov\u00E1 optick\u00E1 komunikace mezi satelity. Av\u0161ak nejprve ka\u017Ed\u00E1 pozemsk\u00E1 stanice mus\u00ED komunikovat se satelitem voln\u00FDm prostorem skrz atmosf\u00E9ru vykazuj\u00EDc\u00ED \u0161irokou \u0161k\u00E1lu \u0161kodliv\u00FDch efekt\u016F produkuj\u00EDc\u00EDch \u0161um a chyby\u00A0v p\u0159en\u00E1\u0161en\u00FDch koherentn\u00EDch a entanglovan\u00FDch stavech. Takov\u00E9 \u0161umov\u00E9 kan\u00E1ly mohou\u00A0plnit svou funkci pouze\u00A0v kombinaci s \u00FA\u010Dinnou korekc\u00ED chyb. V tomto projektu chceme vyvinout technologii kvantov\u00E9 opravy chyb pro koherentn\u00ED kvantov\u00E9 komunikace umo\u017E\u0148uj\u00EDc\u00ED v\u011Brn\u00FD p\u0159enos kvantov\u00FDch stav\u016F sv\u011Btla skrz atmosf\u00E9rick\u00FD kan\u00E1l.\u00A0O\u010Dek\u00E1van\u00E9 v\u00FDsledky maj\u00ED p\u0159\u00EDmou aplikaci v koherentn\u00EDch kvantov\u00FDch komunikac\u00EDch, ale jsou tak\u00E9 velmi zaj\u00EDmav\u00E9\u00A0z obecn\u00E9ho fyzik\u00E1ln\u00EDho\u00A0pohledu." . "2007-07-01+02:00"^^ . "quantum optics" . "Kvantov\u00E1 komunikace se spojit\u00FDmi prom\u011Bnn\u00FDmi skrz \u0161umov\u00E9 kan\u00E1ly" . "15"^^ . "15"^^ . . . " squeezed light" . "GC202/07/J040" . . . . "Quantum communication with continuous variables through noisy channels"@en . "0"^^ . " quantum entanglement" . . "1"^^ .