Laser Production of a Very Slow Monoenergetic Atomic Beam

With use of a resonant, counterpropagating laser beam the velocity of atoms in a neutral, thermal-sodium beam has been reduced to 40 m/s, or 4% of their initial velocity. These atoms have a kinetic energy comparable to the well depth of proposed optical traps. The "temperature" characterizing the atoms' relative motion was reduced to 70 mK.