Obiettivo This project proposes to implement quantum optical techniques for controlling the noise in optical IT, and, beyond this, to explore new concepts which take full advantage of the quantum nature of light.The research addresses the problems of implementing noise free light sources, the design of noiseless couplers and amplifiers for more efficient networks, and the search for new concepts of quantum encoding. Significant results have been obtained in the first year. The emission of squeezed light from second harmonic monolithic resonators can now be stabilized with significant levels of squeezing. Spatial features of squeezing appears to be an new interesting field, worthwhile of experimental investigation, which would lead to noise reduction in images. A high gain noiseless parametric amplifier and a quantum optical tap have been implemented. High efficiency detectors have been designed and used to demonstrate the possibility of quantum communication on long distances.APPROACH AND METHODS The consortium involves seven partners who represent both academic and corporate research. They bring their skills together to examine three kinds of issues relevant to IT: - Light sources with reduced quantum noise. Based on the expertise developed earlier, several types of such light sources will be studied, laser pumped parametric sources, sub-shot noise lasers and lasers with reduced spontaneous emission. - Noiseless amplifiers and couplers. Using phase sensitive amplifiers and couplers allows to circumvent the 3dB limit set by quantum mechanics for the noise added to the amplified or coupled signal. Several of the most promising systems will be investigated in view of application to on-line all optical noiseless amplifiers, optical taps and optical buses. - Reception, device characterisation and quantum protocols. To investigate the processes described above, the search for materials with very small losses, detectors with high quantum efficiency and low noise electronics is expected to lead to interesting by-products by pushing at the limits of tolerance. On the software side, various kinds of squeezed light and pair photons will be explored with regard to encoding reliability or security in quantum optical information systems. POTENTIAL Applications of these concepts are expected to lead to: light sources with lower quantum noise; leading to lower BER (bit error rate) in communications; the implementation of noiseless optical buses for information networks, and to the development of quantum encoding. Campo scientifico natural sciencescomputer and information sciencessoftwarenatural sciencesphysical sciencesquantum physicsquantum opticsnatural sciencesphysical sciencesopticslaser physicsnatural sciencesphysical sciencestheoretical physicsparticle physicsphotons Programma(i) FP3-ESPRIT 3 - Specific research and technological development programme (EEC) in the field of information technologies, 1990-1994 Argomento(i) Data not available Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore Centre National de la Recherche Scientifique (CNRS) Contributo UE Nessun dato Indirizzo 15 Quai Anatole France 75700 Paris Francia Mostra sulla mappa Costo totale Nessun dato Partecipanti (6) Classifica in ordine alfabetico Classifica per Contributo UE Espandi tutto Riduci tutto British Telecom plc (BT) Regno Unito Contributo UE Nessun dato Indirizzo British Telecom Centre 81 Newgate Street EC1A 7AJ London Mostra sulla mappa Collegamenti Sito web Opens in new window Costo totale Nessun dato Centre National d'Études des Télécommunications (CNET) Francia Contributo UE Nessun dato Indirizzo 38-40 rue du Général Leclerc 92131 Issy-les-Moulineaux Mostra sulla mappa Costo totale Nessun dato Centre National de la Recherche Scientifique Francia Contributo UE Nessun dato Indirizzo 91403 Orsay Mostra sulla mappa Costo totale Nessun dato Defence Research Agency (DRA) Regno Unito Contributo UE Nessun dato Indirizzo St Andrews Road WR14 3PS Malvern Mostra sulla mappa Costo totale Nessun dato UNIVERSITAET KONSTANZ Germania Contributo UE Nessun dato Indirizzo Universitaetsstrasse 10 KONSTANZ Mostra sulla mappa Collegamenti Sito web Opens in new window Costo totale Nessun dato Università degli Studi di Genova Italia Contributo UE Nessun dato Indirizzo Via Dodecaneso 35 16146 Genova Mostra sulla mappa Costo totale Nessun dato