Cooling and trapping of atomic strontium

We present a detailed investigation of strontium magneto-optical trap (MOT) dynamics. Relevant physical quantities in the trap, such as temperature, atom number and density, and loss channels and lifetime, are explored with respect to various trap parameters. By studying the oscillatory response of a two-level S-1(0)-P-1(1) Sr-88 MOT, we firmly establish the laser cooling dynamics predicted by Doppler theory. Measurements of the MOT temperature, however, deviate severely from Doppler theory predictions, implying significant additional heating mechanisms. To explore the feasibility of attaining quantum degenerate. alkaline-earth samples via evaporative cooling, we also present the first experimental demonstration of magnetically trapped metastable Sr-88. Furthermore, motivated by the goal of establishing the fermionic isotope Sr-87 as one of the highest-quality, neutral-atom-based optical frequency standards, we present a preliminary study of sub-Doppler cooling in a Sr-87 MOT. A dual-isotope (Sr-87 and Sr-88) MOT is also demonstrated. (C) 2003 Optical Society of America.