MAGNETIZATION AND SPIN-FLIP DYNAMICS OF ATOMS IN OPTICAL LATTICES

We show, experimentally and using quantum Monte Carlo simulations, tha t the quasithermal paramagnetic behavior of cesium atoms in a one-dime nsional lin perpendicular to lin optical lattice is characterized by a spin temperature of twice the zero-field kinetic temperature. The mag netization is maximum and almost perfect when the Zeeman shift of the extreme magnetic sublevels approximately equals half the maximum light shift. The lifetime of magnetization and the laser-cooling time const ant are found to be clearly distinct, the magnetization decay time amo unting to at least three times the cooling time. Using simulations we find that the magnetic-dipole correlation time is approximately propor tional to the angular momentum F of the atoms, while cooling and energ y correlation time constants are approximately independent of F. Our r esults imply that for large F laser cooling within single light-shift potential wells (local cooling) occurs. [S1050-2947(98)51310-8].