We report the experimental realisation of a versatile ring trap for ultracold atoms. The ring geometry is created by the time-averaged adiabatic potential resulting from the application of an oscillating magnetic bias field to a rf dressed quadrupole trap. Lifetimes for a Bose-Einstein condensate in the ring exceed 11s and the ring radius was continuously varied from 50$\mu$m to 261$\mu$m. An efficient method of loading the ring from a conventional TOP trap is presented together with a rotation scheme which introduces angular momentum into the system. The ring presents an opportunity to study the superfluid properties of a condensate in a multiply connected geometry and also has applications for matter-wave interferometry

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We report an experimental realization of ultracold atoms confined in a time-averaged, adiabatic potential (TAAP). This trapping technique involves using a slowly oscillating (∼kHz) bias field to time-average the instantaneous potential given by dressing a bare magnetic potential with a high-frequency (∼MHz) magnetic field. The resultant potentials provide a convenient route to a variety of trapping geometries with tunable parameters. We demonstrate the TAAP trap in a standard time-averaged orbiting potential trap with additional Helmholtz coils for the introduction of the radio frequency dressing field. We have evaporatively cooled 5 × 10 4 atoms of 87 Rb to quantum degeneracy and observed condensate lifetimes of longer than 3 s.

We report two novel techniques for cooling and rotating Bose-Einstein condensates in a dilute rubidium vapour that highlight the control and versatility afforded over cold atom systems by time-averaged adiabatic potentials (TAAPs). The intrinsic loss channel of the TAAP has been successfully employed to evaporatively cool a sample of trapped atoms to quantum degeneracy. The speed and efficiency of this process compares well with that of conventional forced rf-evaporation. In an independent experiment, we imparted angular momentum to a cloud of atoms forming a Bose-Einstein condensate by introducing a rotating elliptical deformation to the TAAP geometry. Triangular lattices of up to 60 vortices were created. All findings reported herein result from straightforward adjustments of the magnetic fields that give rise to the TAAP.