Meta-stable 1-D gases of polar molecules with attractive dipole forces

Robin Côté

Andrea Simoni, Jean–Michel Launay

Jason N. Byrd, John A. Jr. Montgomery, Robin Côté

We explore one-dimensional samples of ultracold polar molecules with attractive dipole-dipole interactions and show the existence of a repulsive barrier caused by a strong quadrupole interaction between molecules. This barrier can stabilize a gas of ultracold KRb molecules and even lead to long-range wells supporting bound states between the molecules. The properties of these wells can be controlled by external electric fields, allowing the formation of long polymerlike chains of KRb and studies of quantum phase transitions by varying the effective interaction between molecules. We discuss the generalization of those results to other systems.

Reuben R. W. Wang, John L. Bohn

We discuss the influence of collisions on the dynamics of an ultracold gas whose constituents interact via dipolar forces. This dynamics is governed by the elastic scattering cross section of the molecules, which is to some extent under the experimentalist's control. We compare side-by-side several different situations, highlighting their similarities and differences. These situations are collisions between: 1) point dipoles; 2) electric-field-shielded polar molecules; and 3) microwave-shielded polar molecules, including the effect of microwave ellipticity.

Andrea Simoni, Jean–Michel Launay

S. Stringari, John L. Bohn, Eugene Demler +5 more

Recently ground state polar molecules have been successfully realized using stimulated Raman adiabatic passage (STIRAP) technique, which has stimulated new experimental activities along this direction in many laboratories. It is very promising that a stable and quantum degenerate gas of polar molecules can be realized in the near future. Such polar molecules have a large permanent electric dipole moment and hence strong long-range dipolar interaction effects in the presence of an electric field, giving rise to new few- and many-body phenomena that are absent in the traditional atomic systems explored so far.