Deceleration, trapping, and two-photon cooling of calcium atoms

We report on a system for atomic beam deceleration and magneto-optical trapping of calcium atoms that uses the 1S0–1P1 transition, in which a single laser is used to trap and slow the atoms. The slower laser beam is focused near the magneto-optical trap’s center, which has a waist size much smaller than the atomic cloud such that its influence on the trapped atoms is greatly reduced. We also investigate the theoretical possibility of cooling by use of a two-photon (4s2)1S0–(4s5s)1S0 transition. Excitation near resonance with the 1P1 level results in an equilibrium temperature seven times smaller than the Doppler limit of the 1S0–1P1 transition.