General Physics Seminar Thursday 18 April 2002


New physics with ultracold polar molecules

Gora Chliapnikov

Quantum Gases Group, FOM Institute for Atomic and Molecular Physics (AMOLF), Amsterdam, The Netherlands



I will discuss new physics that one expects in gases of cold polar molecules. Being electrically polarized these molecules interact with each other via long-range anisotropic dipole-dipole forces. Therefore, an effective mean field strength in trapped gases depends on the trapping geometry. This has a strong influence on the behavior of the gas in the regime of quantum degeneracy. In the case of bosonic molecules the shape of the trapped Bose-Einstein condensate is quite different from the shape of the trap, and one has a possibility to manipulate the condensate by varying the trapping geometry. The stability of the condensate also depends on the geometry. Thus, condensates of polar molecules are expected to be truly different from ordinary atomic condensates.

I will discuss these issues and raise the question of dynamical stability of trapped dipolar condensates. In the end I will make a link to cold fermionic molecules and discuss prospects of superfluid BCS transition in these systems.