Stochastic laser cooling enabled by many-body effects

A novel laser cooling mechanism based on many-body effects is presented. The method can be applied to the cooling of a large class of atoms and molecules at a higher density than commonly excepted by existing methods. The cooling mechanism relies on the collective encounter of particles and light. Stochastic events between the particles and photons, as well as a collective effect, give rise to energy transfer between these media. Such a mechanism relies on multiple light-matter encounters, therefore requiring a sufficient particle density, ρ ∼ 10¹⁴ cm^-3. This is an advantage for experiments where a high phase space density is required. A second tuning laser can be added, increasing the applicability to many types of atoms and molecules. This tuning laser changes the inter-particle potential by inducing an AC Stark effect. As a result, the required trapping density can be reduced to ρ ∼ 10⁶ cm^-3. Simulations of phase space distributions were performed, comparing different particle densities, trap potentials and light field intensity profiles. The modelling shows efficient cooling rates up to 10 ²K s^-1 for a dense ensemble of ⁸⁷Rb atoms, and cooling rates of up to 6 • 10 ² K s^-1 when adding an additional tuning source.