Deceleration of a calcium atomic beam with a frequency-doubled diode laser

A calcium atomic beam has been decelerated by a single extended-cavity diode laser, frequency doubled to 423 nm. A potassium niobate crystal is placed in an external power buildup cavity, and the second-harmonic laser beam, counterpropagating with the atomic beam, is tuned into resonance with the strong 1S0-1P1 transition of calcium. For input power of 78 mW at 846 nm, we generate 22 mW at 423 nm after correction for the reflectivity of our cavity output coupler. To keep the atoms always in resonance during the deceleration process, the Zeeman tuning technique was used.