Objective Quantum communication aims to transmit a quantum state (e.g. entangled states) between two distant locations.Unfortunately, the losses during the transmission in optical fiber or in free space are detrimental to the entanglement and make direct practical implementation of long distances communication unrealistic.In classical communication this problem can be solved using amplifiers but this approach is forbidden by quantum mechanics in most of the cases.However the concept of quantum repeaters offers the possibility to solve this problem based on the idea that entanglement over a given distance can be created by entanglement swapping starting from two entangled pairs, covering only half the distance.This method implies the ability to store a quantum state and thus requires the availability of long-lived quantum memory.The long-term goal in the field is therefore to improve over the direct transmission rate using a quantum repeater approach.Indeed, quantum memories have been demonstrated in several materials using various protocols, but the practical implementation is still a far reaching goal.During this project, I will study two very promising protocols : the gradient-echo-memory (outgoing phase) and the atomic-frequency-comb memory (returning phase) with three different materials : hot atomic vapor, cold atoms, rare-earth crystals.Time and space channels multiplexing are key features to improve over the direct transmission rate,therefore this project focuses on the temporal and spatial multimode behavior of these memories.During the outgoing phase, I will build a gradient-echo-memory to store quantum correlated images.This is expected to be the first demonstration of multispatial mode quantum memory.During the returning phase depending of the experimental progress of the Geneva's group, I will work on temporal multiplexing and practical implementation of a quantum repeater, which fits perfectly within the European project leaded by the group : QuRep. Fields of science engineering and technologymaterials engineeringfibersnatural sciencesphysical sciencesquantum physicsnatural sciencesphysical sciencesopticsfibre optics Programme(s) FP7-PEOPLE - Specific programme "People" implementing the Seventh Framework Programme of the European Community for research, technological development and demonstration activities (2007 to 2013) Topic(s) FP7-PEOPLE-2011-IOF - Marie Curie Action: "International Outgoing Fellowships for Career Development" Call for proposal FP7-PEOPLE-2011-IOF See other projects for this call Funding Scheme MC-IOF - International Outgoing Fellowships (IOF) Coordinator UNIVERSITE DE GENEVE EU contribution € 245 520,60 Address RUE DU GENERAL DUFOUR 24 1211 Geneve Switzerland See on map Region Schweiz/Suisse/Svizzera Région lémanique Genève Activity type Higher or Secondary Education Establishments Administrative Contact Nicolas Gisin (Prof.) Links Contact the organisation Opens in new window Website Opens in new window Total cost No data
