Anisotropy of optical suppression in photoassociative ionization collisions within a slow, collimated sodium atom beam
نویسندگان
چکیده
We report the observation of polarization anisotropy in the optical suppression of photoassociative ionization (PAI) collisions. Binary collisions occur within a tightly collimated and optically cooled velocity group of a single sodium beam. A laser beam, blue-detuned with respect to the atomic resonance transition, crosses the atomic beam and suppresses the PAI rate. We measure this suppression as a function of intensity and electric field vector aligned parallel or perpendicular to the atomic beam axis. Quantum close-coupling and multichannel curve-crossing calculations of model systems yield insight into the nature of the anisotropy and are in reasonable agreement with the measurements. PACS. 32.80.Pj Optical cooling of atoms; trapping – 34.50.Rk Laser-modified scattering and reactions
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