Abstract: Controllable dipole-dipole interaction between polar molecules in an optical trap lies at the heart of many proposals to exploit entanglement as an essential resource for strongly correlated many-body states and quantum information processing.  

Even though polar molecules interact at large separations via dipole-dipole interaction, at shorter distances Van der Waals forces will prevail. I study both vibrationally dependent collisional and dipole-dipole interaction between cold polar molecules and with their constituent atoms. The collisional interaction coefficients are obtained by integrating the product of the dynamic polarizabilities over imaginary frequencies.

These data can be used to estimate limits on the collisional lifetime of molecules in optical traps and find microscopic mechanisms by which the losses occur. The ultimate goal is to find optimal experimental conditions to diminish these collisional losses.