An electro-optical trap for polar molecules

A detailed treatment of an electro-optical trap/tweezer for polar molecules, realized by embedding an optical trap within a uniform electrostatic field, is presented and the trap's properties discussed. The electro-optical trap offers significant advantages over an optical trap that include an increased trap depth and conversion of alignment of the trapped molecules to marked orientation. Tilting the polarization plane of the optical field with respect to the electrostatic field lifts the degeneracy of the M states of the trapped molecules. These and other features of the electro-optical trap are explained in terms of the eigenproperties of the polar and polarizable molecules subject to the combined permanent and induced electric dipole interactions at play.