Theme 1 – Coherence and quantum entanglement: from atoms to mesoscopic systems
During the 20th Century, quantum mechanics gradually provided an understanding of the properties of atoms, materials, and then of increasingly complex physical systems.
The strangeness of the quantum world, notably with non-local intrication between physically separate systems and superpositions of quantum states for macroscopic systems, passed from a curiosity status to the status of a real technical resource during the period 1980-1990.
Demonstration of quantum intrication, shown by the violation of Bell's inequalities, was actually followed shortly by very appealing proposals for exploiting this intrication in the field of information, with cryptography and quantum computation, as well as in that of highly accurate devices, with atomic clocks and interferometry with non-classical states.
New methods for cooling atoms with a laser and progress in micro- and then nano-manufacturing have allowed the production of quantum systems involving and combining atoms and/or molecules, which are intrinsically quantum objects, with electric circuits, which may themselves behave as completely artificial quantum atoms. Quantum physics is presently in a phase for applying and making use of the new concepts put forward during the recent decades, with full development of similar problems in fields which had hitherto remained quite separate.
Our goal is to go deeper in the understanding of quantum coherence and intrication, by merging the skills and advances of condensed matter physics and that of diluted media (atomic, molecular and optical physics), both highly developed in the Palaiseau-Orsay-Saclay triangle. The question is of designing and applying new quantum systems for putting to use the combination of coherence and intrication, with ambitious goals in the long term. Let us mention here the possibility of developing lasers, interferometers with atomic matter waves, systems with individually controlled interacting atoms, devices based on degenerate quantum gases, molecular circuits in which electric transport would be controlled at a molecular scale, and circuits with quantum bits prefiguring actual quantum information processors.
Moreover, collaborations with young regional start-ups are already foreseen for developing new advanced equipment, for example inertial sensors with matter waves, by relying on existing industrial platforms.
