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We demonstrate an efficient scheme for continuous trap loading based upon spatially selective optical pumping. We discuss the case of $^{1}$S$_{0}$ calcium atoms in an optical dipole trap (ODT), however, similar strategies should be applicable to a wide range of atomic species. Our starting point is a reservoir of moderately cold ($approx 300 mu$K) metastable $^{3}$P$_{2}$-atoms prepared by means of a magneto-optic trap (triplet-MOT). A focused 532 nm laser beam produces a strongly elongated optical potential for $^{1}$S$_{0}$-atoms with up to 350 $mu$K well depth. A weak focused laser beam at 430 nm, carefully superimposed upon the ODT beam, selectively pumps the $^{3}$P$_{2}$-atoms inside the capture volume to the singlet state, where they are confined by the ODT. The triplet-MOT perpetually refills the capture volume with $^{3}$P$_{2}$-atoms thus providing a continuous stream of cold atoms into the ODT at a rate of $10^7 $s$^{-1}$. Limited by evaporation loss, in 200 ms we typically load $5 times 10^5$ atoms with an initial radial temperature of 85 $mu$K. After terminating the loading we observe evaporation during 50 ms leaving us with $10^5$ atoms at radial temperatures close to 40 $mu$K and a peak phase space density of $6.8 times 10^{-5}$. We point out that a comparable scheme could be employed to load a dipole trap with $^{3}$P$_{0}$-atoms.
We present an effective and fast (few microseconds) procedure for transferring ultra-cold atoms from the ground state in a harmonic trap into the desired bands of an optical lattice. Our shortcut method is a designed pulse sequence where the time dur
One important factor which determines efficiency of loading cold atoms into an optical dipole trap from a magneto-optical trap is the distance between the trap centers. By studying this efficiency for various optical trap depths (2--110 mK) we find t
We report a method for loading cold atoms into an optical trap with high initial phase-space density (PSD). When the trap beam is overlapped with atoms in optical molasses of optimized parameters including large cooling beam detuning compared with co
Examination of loading the isotopes $^{85}$Rb and $^{87}$Rb simultaneously into a shallow far-off-resonance trap (FORT) has revealed an unexpected decrease in maximum atom number loaded as compared to loading either isotope alone. The simultaneous lo
We present studies of strong coupling in single-photon photoassociation of cesium dimers using an optical dipole trap. A thermodynamic model of the trap depletion dynamics is employed to extract absolute rate coefficents. From the dependence of the r