Laser Cooling and Trapping of Neutral Atoms.

This report demonstrated the deceleration of an atomic sodium beam by means of photon pressure. Near resonant light from a counter-propagating cooling laser beam is absorbed by the atoms, causing them to slow down. The deceleration is observed by means of Doppler velocity analysis using a second probe laser. We modulate the cooling laser on and off while using time resolved observation of the fluorescence induced by the second laser this allows observation of the effects of the cooling laser when the cooling laser light is not present. We have used circularly polarized light and a strong magnetic field in the direction of the cooling laser to avoid optical pumping of the atoms, a process which limits the amount of momentum which can be transferred to the atoms.