Isotropic light versus six-beam molasses for Doppler cooling of atoms from background vapor: Theoretical comparison

Abstract

We present a 3D theoretical comparison between the radiation-pressure forces exerted on an atom in an isotropic light cooling scheme and in a six-beam molasses. We demonstrate that, in the case of a background vapor where all the space directions of the atomic motion have to be considered, the mean cooling rate is equal in both configurations. Nevertheless, we also point out what mainly differentiates the two cooling techniques: the force component orthogonal to the atomic motion. If this transverse force is always null in the isotropic light case, it can exceed the radiation-pressureforce longitudinal component in the six-beam molasses configuration for high atomic velocities, hence reducing the velocity capture range.

Nearly nondestructive thermometry of labeled cold atoms and application to isotropic laser cooling

“…And then according to Eq. ( 3), from the collected data we can estimate that |β sub /β OM | 1, where β OM is the damping coefficient of typical Doppler cooling process in 1D optical molasses [53].…”