Microwave-Optical Stark-Sisyphus Deceleration

We propose a general method to decelerate beams of polyatomic molecules. The technique uses inhomogeneous static electric fields, microwave adiabatic passage, and optical pumping to remove kinetic energy. It is applicable to any polyatomic molecule possessing an electric dipole moment and reasonably diagonal Franck-Condon factors. We identify over a dozen laser-coolable molecules for which this method is predicted to remove between 1 and 2 K of energy per deceleration stage, thus requiring about 10 photon scatters to slow to rest an optimized cryogenic buffer-gas beam. By way of example, we theoretically evaluate the decelerator's performance for two specific molecules, YbOH and CaOCH$_3$.