Cooling atoms in an optical trap by selective parametric excitation

Cooling Atoms in an Optical Trap by Selective Parametric Excitation

Comment on "direct measurement of the oscillation frequency in an optical-tweezers trap by parametric excitation".

Direct measurement of the oscillation frequency in an optical-tweezers trap by parametric excitation.

We demonstrate a novel technique for direct measurement of the oscillation frequency in an optical-tweezers trap. The technique uses the phenomenon of parametric resonance in an oscillator when the stiffness of the trapping potential is modulated. The trapped particle is a strongly damped oscillator; hence, the signature of parametric resonance is not an increase in the amplitude but an increas...

Magneto-optical cooling of atoms.

We propose an alternative method to laser cooling. Our approach utilizes the extreme brightness of a supersonic atomic beam, and the adiabatic atomic coilgun to slow atoms in the beam or to bring them to rest. We show how internal-state optical pumping and stimulated optical transitions, combined with magnetic forces, can be used to cool the translational motion of atoms. This approach does not...

Sympathetic cooling with two atomic species in an optical trap.

We simultaneously trap ultracold lithium and cesium atoms in an optical dipole trap formed by the focus of a CO2 laser and study the exchange of thermal energy between the gases. The optically cooled cesium gas efficiently decreases the temperature of the lithium gas through sympathetic cooling. Equilibrium temperatures down to 25 microK have been reached. The measured cross section for thermal...