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We have successfully demonstrated an integrated optical system for collecting the fluorescence from a trapped ion. The system, consisting of an array of transmissive, dielectric micro-optics and an optical fiber array, has been intimately incorporated into the ion-trapping chip without negatively impacting trapping performance. Epoxies, vacuum feedthrough, and optical component materials were carefully chosen so that they did not degrade the vacuum environment, and we have demonstrated light detection as well as ion trapping and shuttling behavior comparable to trapping chips without integrated optics, with no modification to the control voltages of the trapping chip., Comment: 14 pages, 12 figures

Individual laser cooled atoms are delivered on demand from a single atom magneto-optic trap to a high-finesse optical cavity using an atom conveyor. Strong coupling of the atom with the cavity field allows simultaneous cooling and detection of individual atoms for time scales exceeding 15 s. The single atom scatter rate is studied as a function of probe-cavity detuning and probe Rabi frequency, and the experimental results are in good agreement with theoretical predictions. We demonstrate the ability to manipulate the position of a single atom relative to the cavity mode with excellent control and reproducibility., Comment: 10 pages, 5 figures, submitted to Phys. Rev. Lett

Individual atoms are deterministically loaded into a high finesse optical cavity using an optical lattice. With cavity-assisted cooling, long interaction times of the atoms with the cavity field are achieved.

Ultracold $^{87}$Rb atoms are delivered into a high-finesse optical micro-cavity using a translating optical lattice trap and detected via the cavity field. The atoms are loaded into an optical lattice from a magneto-optic trap (MOT) and transported 1.5 cm into the cavity. Our cavity satisfies the strong-coupling requirements for a single intracavity atom, thus permitting real-time observation of single atoms transported into the cavity. This transport scheme enables us to vary the number of intracavity atoms from 1 to $>$100 corresponding to a maximum atomic cooperativity parameter of 5400, the highest value ever achieved in an atom--cavity system. When many atoms are loaded into the cavity, optical bistability is directly measured in real-time cavity transmission., 4 figures, 4 pages

We measure spin mixing of $F=1$ and $F=2$ spinor condensates of $^{87}\mathrm{Rb}$ atoms confined in an optical trap. We determine the spin mixing time to be typically less than 600 ms and observe spin population oscillations. The equilibrium spin configuration in the $F=1$ manifold is measured for different magnetic fields and found to show ferromagnetic behavior for low field gradients. An $F=2$ condensate is created by microwave excitation from the $F=1$ manifold, and this spin-2 condensate is observed to decay exponentially with time constant 250 ms. Despite the short lifetime in the $F=2$ manifold, spin mixing of the condensate is observed within 50 ms.

Given the tremendous impact of BEC research in last 7 years and the continued growth of the field, it is important to explore different methods for reaching BEC, particularly methods that offer new capabilities, simplicity, or speed. We have recently demonstrated such a method by creating a Bose condensate of Rb atoms directly in a crossed-beam optical dipole force trap using tightly focused CO2 gas laser beams [1]. In the broader scope of research with ultracold degenerate gases, our system stands out for several reasons. First, all-optical BEC provides the first new path to achieving BEC since the first pioneering demonstrations [2-4], and it is surprising simple and an order of magnitude faster than standard BEC experiments. Also, optical trapping potentials are essentially spin-independent and hence are well suited for studying the formation and dynamics of spinor condensates. Finally, we can engineer a rich variety of spatial confinements, including large period oneand threedimensional lattices that offer the possibility of optically resolving individual lattice sites. All-optical methods of reaching the BEC phase transition have been pursued since the early days of laser cooling. Despite many impressive developments beyond the limits set by Doppler cooling, the best previous efforts yielded atomic phase space densities a factor of 3 away from the BEC transition [5, 6]. Hence, optical traps have played only a supporting role in BEC experiments. The MIT group used a magnetic trap with an ‘optical dimple’ to reversibly condense a magnetically confined cloud of atoms evaporatively cooled to just above the phase transition [7]. Additionally, Bose condensates created in magnetic traps have been successfully transferred to shallow optical traps for further study [8]. In all these cases, however, magnetic traps provided the principle increase of phase space density (by factors up to 10) to the BEC transition. Evaporative cooling in optical traps was first demonstrated in 1994, where, starting with only 5000 atoms, a phase space density increase of a factor of ~30 was realized [9]. Whereas the first demonstrations of evaporative cooling of alkali atoms in magnetic traps lead quickly to the observation of BEC, the progress in optical traps was slower. A principle challenge faced by all-optical traps is that the small