Magnetic Surface Microtraps for Two-Species Bose-EinsteinCondensations

We propose a novel magnetic surface microtraps (i.e., a double Z-wire trap) for the study of two-species Bose-Einstein condensations. The spatial distributions of the magnetic fields from the double Z-wire configurations and their gradients and curvatures are calculated and analysed. The result shows that the proposed surface trap has double magnetic wells and can be continuously changed into a single-well trap by reducing the current in a straight wire, and the maximum field gradient greater than 5 x 10⁴G/cm and the maximum field curvature (at each trap center) greater than 2.5 x 10⁷G/cm² can be generated in our double-well traps, which can be used to realize two-species Bose-Einstein condensations and to study the properties of double-well Bose-Einstein condensations and so on.