Quantum dynamics of ultracold atomic gases far from equilibrium

• Applicant: Professor Dr. Thomas Gasenzer
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2006 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 32193338

Atomic physics has been revolutionized during the past decades, especially through the advent of modern cooling an trapping technologies. Highlights of this evolution are the preparation of quantum-degenerate ultracold atomic gases, i.e., of Bose-Einstein condensates or degenerate Fermi gases. The geometry of the atom traps can be varied almost at will and on very fast time scales. With this, as well as through strong interatomic forces induced by external electromagnetic fields, the atom gases can be brought far out of equilibrium. While many phenomena in ultracold atomic gases allow for complementary studies of their counterpart in solid state physics, with this, as compared to electron gases in solids, studies of the far-from-equilibrium dynamics over short and intermediate time scales are possible. The theory of this dynamics remains still in its beginnings. The projects outlined in this application aim at progressing beyond standard dynamical quantum field theoretical approximations, which in general require weak interatomic forces. Novel, most advanced quantum-field theoretical procedures on the basis of action-functional techniques will be extended for trapped ultracold atomic gases. The aim is to make these methods accessible to experimental verification, which has not been possible in any other field in physics. Such a precise experimental verification has important potential impact on other areas like heavy ion collisions or cosmology, where non-equilibrium methods are needed and much more difficult to check experimentally. The projects focus on the dynamics in one-dimensional traps and optical lattices, the formation of quantum-degenerate phases in ultracold gases, as well as the dynamics of the transition from a molecular condensate to a superfluid of Cooper pairs in a Fermi gas. These key phenomena have important potential applications, e.g., in quantum information technology, for the definition of new time standards, and for precision measurements in atomic and molecular physics.

• DFG Programme: Research Grants