Optical Stark Decelerator for Molecules

We demonstrate a single stage optical Stark decelerator for neutral molecules which is capable of reducing the translational energy of benzene molecules within a molecular beam by 15% in a single pulsed Gaussian optical field of 15 ns duration. The change in velocity induced by the optical potential is measured by the change in the time of flight of benzene molecules ionized by a second optical field after the slowing field is turned off. A maximum reduction in the velocity of $25\mathrm{m}/\mathrm{s}$ was measured using a single Gaussian beam with a peak intensity of $1.6\times {10}^{12}\mathrm{W}/{\mathrm{c}\mathrm{m}}^2$ corresponding to a maximum well depth of 253 K.