We describe the theoretical advances that influenced the experimental creation of vibrationally and translationally cold polar 40K87Rb molecules [Nature Phys. 4, 622 (2008), Science 322, 231 (2008)]. Cold molecules were created from very-weakly bound molecules formed by magnetic field sweeps near a Feshbach resonance in collisions of ultra-cold 40K and 87Rb atoms. Our analysis include the multi-channel bound-state calculations of the hyperfine and Zeeman mixed X and a vibrational levels. We find excellent agreement with the hyperfine structure observed in experimental data. In addition, we studied the spin-orbit mixing in the intermediate state of the Raman transition. This allowed us to investigate its effect on the vibrationally-averaged transition dipole moment to the lowest ro-vibrational level of the X state. Finally, we obtained an estimate of the polarizability of the initial and final ro-vibrational states of the Raman transition near frequencies relevant for optical trapping of the molecules.
Citation: New Journal of Physics
Pub Type: Journals
ultracold molecules, multi-channel calculations, polarizability, KRb, molecular hyperfine mixing, spin-orbit interactions