Thanks to the recent development of methods to manipulate atoms by electromagnetic fields, quantum gases at very low temperature can be routinely produced. Teams working on this topic are interested in theoretical and experimental studies of fermionic and bosonic quantum gases.
The rapid growth of methods for laser cooling and trapping of atoms opened the field of ultracold quantum gases. In these systems, the many-body behavior is very different from classical physics. To reach this quantum regime, the typical length scale of the atomic wave packet, the de Broglie wavelength, has to be larger than the mean interparticle distance. The quantum statistics, bosonic or fermionic, also lead to very different behaviors. Bosons undergo Bose-Einstein condensation and they accumulate in the same quantum state and, thus, get an extended phase coherence over the full size of the system. Fermions, according to Pauli principle, cannot occupy the same quantum state: attractive interactions are necessary to reach a superfluid phase, analogous to superconducting phases observed in metals and high critical temperature superconductors.
An important perspective of our work, both from the experimental and theoretical points of view, is to use these very well controlled systems to simulate problems of condensed matter physics which are not completely understood yet.
The Ultracold Fermi Gases team uses fermion gases, especially in the unitary regime, to study superfluidity and thermodynamical properties. Systems composed of fermion/boson or fermion/fermion mixtures are also under investigation.
The Bose-Einstein Condensates team studies quantum gases in various situations: in low dimensions, with a spin degree of freedom or when subjected to spin or orbital magnetism.
The Atom Chips team uses miniaturized systems, such as atoms chips or optical cavities to manipulate Bose-Einstein condensates. These systems are used for quantum electrodynamics and metrology experiments.
The Complex Quantum Systems team focuses on the studies of transport and localization properties in chaotic or disordered systems in the interaction regime. They consider light wave propagation in ultracold atomic clouds but also matter waves in disordered potentials.
Ultracold Fermi Gases
Permanent staff : Yvan Castin, Frédéric Chevy, Christine Guerlin, Christophe Salomon, Félix Werner, Tarik Yefsah
Permanent staff : Jérôme Beugnon, Claude Cohen-Tannoudji, Jean Dalibard, Fabrice Gerbier, Michèle Leduc, Sylvain Nascimbene
Permanent staff : Jean Hare, Romain Long, Jakob Reichel, Alice Sinatra
Complex Quantum Systems