ABSTRACT Dual‐species cold atom systems are drawing increasing attention in the research of interactions in degenerate cold gases. In this article, we report a method for the simultaneous cooling of 85 Rb and 87 Rb atoms in an integrating sphere system. Optimal parameters were determined for cooling laser power and cooling laser detuning to maximize the number of cold atoms and minimize the collision‐induced loss rate coefficients. The 87 Rb atoms at a temperature of 82 with an atomic number of , and 85 Rb atoms at a temperature of 87 with an atomic number of are simultaneously cooled. Our results offer an approach for the simultaneous cooling of two‐isotope mixtures, featuring a large atomic number, low temperature, and no requirement for an external magnetic field. This method holds significant potential for applications in quantum precision measurement, such as gravity gradiometers and cold atomic magnetometers.
We present an efficient cooling scheme for fermionic
40K atoms, using laser light red and blue detuned with respect to the
D2 and
D1 principle flourescence lines, respectively. The cooling scheme is found to significantly increase the saturation level for loading of a
40K magneto-optical trap (MOT), resulting in increased atom numbers or decreased cycle times. While the attainable
40K atom number is approximately doubled if exclusively
40K atoms are cooled, the scheme is particularly powerful for dual-species MOTs, for example, if
40K and
87Rb atoms are cooled simultaneously in the same MOT configuration. The typical atom losses due to light-assisted hetero-nuclear collisions between
40K and
87Rb seem to be reduced giving rise to a threefold improvement of the
40K atom number as compared to that in a conventional dual-species MOT, operating merely with
D2 light. Our scheme can be a useful extension to most dual-species experiments, aiming to reach simultaneous degeneracy of both species.
Abstract This study establishes a magneto-optical trap system for trapping cold atoms. By employing image processing techniques, we identified the actual size of the trapped cold atom cluster and assessed the variations in the number of trapped cold atoms. We have successfully trapped for both 87Rb and 85Rb atoms. Optimal parameters were determined for cooling laser power, cooling laser detuning, repumping laser power, and magnetic field current to maximize the number of trapped cold atoms. The optimization results and methods presented in this paper can be applied to validate the equivalence principle and in dual-test quantum gravimeters.
We present an efficient cooling scheme for fermionic
40K atoms, using laser light red and blue detuned with respect to the D2 and D1 principle fluorescence lines, respectively. The cooling scheme is found to significantly increase the saturation level for loading of a
40K magneto-optical trap (MOT), resulting in increased atom numbers or decreased cycle times. While the attainable
40K atom number is approximately doubled if exclusively
40K atoms are cooled, the scheme is particularly powerful for dual-species MOTs, for example, if
40K and
87Rb atoms are cooled simultaneously in the same MOT configuration. The typical atom losses due to light-assisted heteronuclear collisions between
40K and
87Rb seem to be reduced, giving rise to a threefold improvement of the
40K atom number as compared to that in a conventional dual-species MOT, operating merely with D2 light. Our scheme can be a useful extension to most dual-species experiments, aiming to reach simultaneous degeneracy of both species.
In this paper, the theory of atomic cooling in an integrating sphere is studied. During designing an integrating sphere system, the effects of the parameters of the sphere on the cooling, including the reflectivity of the material, the shape of the sphere and holes in the sphere have been considered carefully. The experiment of 87Rb atomic cooling in an integrating sphere was performed. The experimental results show that the atoms in the integrating sphere are cooled down evidently. And the relation between the detuning of the cooling laser and the absorption signal of cold atoms was measured.
Abstract We describe a three-dimensional (3D) magneto-optical trap (MOT) capable of simultaneously capturing 85Rb and 133Cs atoms. Unlike conventional setups, our system utilizes two separate laser systems that are combined before entering the vacuum chamber, enabling the simultaneous trapping of two different atomic species. We trapped 85Rb and 133Cs atoms using relatively low total power: 8 mW cooling and 4 mW repump for 85Rb, and 7.5 mW cooling and 1.5 mW repump for 133Cs. The number of trapped atoms was 1.6 × 108 for 85Rb and 1.4 × 108 for 133Cs. The optical depths were 3.71 for 85Rb and 3.45 for 133Cs. The temperature of trapped atoms was ∼200 μK for 85Rb and ∼200 μK for 133Cs. Our 3D MOT setup allows full horizontal optical access to the trapped atomic ensembles without spatial interference from the trapping or repump laser beams. Our vacuum system is also quite simple, avoiding much of the complexity typically encountered in similar dual-species systems. However, the red detuning of the cooling laser used for atomic trapping in our system is relatively small, leaving room for further optimization. This system offers a versatile platform for exploring complex phenomena in ultracold atom physics, such as Rydberg molecule formation and interspecies interactions.