Optical Stark decelerator for molecules with a traveling potential well

We propose a versatile scheme to slow supersonically cooled molecules using a decelerating potential well, obtained by steering a focusing laser beam onto a pair of spinning reflective mirrors under a high-speed brake. The longitudinal motion of molecules in the moving red-detuned light field is analyzed and their corresponding phase-space stability is investigated. Trajectories of CH4 molecules under the influence of the potential well are simulated using the Monte Carlo method. For instance, with a laser beam of power 20 kW focused onto a spot of waist radius 40-100 μm, corresponding to a peak laser intensity on the order of ∼108W/cm2, a CH4 molecule of ∼250m/s can be decelerated to ∼10m/s over a distance of a few centimeters on a time scale of hundreds of microseconds.