Ratchet-based magnetic micropump

Cold atoms in atom wires may be transported, along large distances and with selectable direction, by modifying only the shape of the physical wire and the time dependence of its electric current in a basic atom wire trap. The design of this "magnetic micropump" is based on the ratchet concept. Its transport of cold atoms is shown by symmetry analysis and by direct numerical simulation. The numerical simulation should be considered as proof of principle; more physically realistic designs may be required to achieve transport in experiment. The micropump design could also be used to transport magnetised beads in microfluidic applications.