In this talk, I will present our recent results on the coherent guiding, and dispersion management of atomic Bose-Einstein condensates (BEC) in extremely smooth time-averaged adiabatic potential (TAAP) rings. This study is important for the construction of atomtronic rotation sensors, and on the fundamental side: study of superfluidity much above the critical velocity. In the first experiment, BECs are loaded in a tilted ring trap and then accelerated up to very high angular speeds (16 times than their speed of sound). Subsequently the matter-waves are transported at a constant angular speed for up to 40 cm long distances. In a second case, after accelerating the BECs we launch them into a horizontal ring waveguide. Due to the absence of azimuthal confinement the atom cloud rotates and expand simultaneously. We perform atom optics to achieve long distance compact guiding of BECs. The slowest expansion of the guided ultracold atomic gas corresponds to a few nanoKelvin temperature.
Host: Nir Navon (nir.navon@yale.edu)