Solitary-wave micro-motion in a TOP trap

Katharine Challis

Department of Physics, University of Otago, PO Box 56, Dunedin, New Zealand

We present a theoretical analysis of micro-motion in a time-averaged orbiting potential trap, including condensate nonlinearity. The trapping potential is systematically reduced to an approximate form within which solitary-wave solutions of the Gross-Pitaevskii equation are found. A particular class of such solitary-wave solutions are eigenstates of the system in a circularly translating frame and these states allow us to characterize condensate micro-motion and identify the system ground state. Our treatment is then used to provide a simple theoretical model for Bragg spectroscopy in a time-averaged orbiting potential trap, which numerical calculations verify.