Ionizing Collisions in the Optical Lattice of Metastable Krypton and Argon Atoms

Abstract

Ionizing collisional loss rate of the metastable argon and krypton atoms in an optical lattice is compared with the rate of atoms in free space as a function of lattice laser detuning. Contrary to a simple picture of the isolation of atoms by the lattice potential, our experimental result shows that the collision rate in optical lattice is always larger than that in free space except at a large laser detuning of ∼10 3 transition linewidth. Comparing the experimental result with the theoretical values that are derived from the classical trajectory calculation of the atom, we found that the optical pumping to non-trapped adiabatic potential surface prevents the collision suppression because it keeps the number of non-trapped atoms to a finite value even at low excitation rate.