Purely optical macroscopic trap for alkaline-earth and similar atoms

Abstract

We consider laser cooling and trapping of alkaline-earth and similar atoms in a bichromatic field resonant to a closed optical transition 1S0→1P1 or 1S0→3P1. It is shown that new kinetic effects emerge compared to monochromatic fields, enabling the formation of a deep macroscopic trap capable of capturing and cooling neutral atoms to sub-Doppler temperatures. Such a purely optical macroscopic trap can serve as an alternative to the well-known magneto-optical trap and can be used in applications requiring minimization of the magnetic field in the cold atom cloud region. The obtained results are of interest for the new generation of quantum sensors and optical frequency standards.