Microelectromagnets for trapping and manipulating ultracold atomic quantum gases

We describe the production and characterization of microelectromagnets made for trapping and manipulating atomic ensembles. The devices consist of seven fabricated parallel copper conductors 3 μm thick, 25 mm long, with widths ranging from 3 to 30 μm, and are produced by electroplating a sapphire substrate. Maximum current densities in the wires up to ${\text{6.5×10}}^6\hspace{0.17em}{\mathrm{A\hspace{0.17em}cm}}^{\text{−2}}$ are achieved in continuous mode operation. The device operates successfully at a base pressure of ${10}^{\text{−11}}\hspace{0.17em}\mathrm{mbar}.$ The microstructures permit the realization of a variety of magnetic field configurations and, hence, provide enormous flexibility for controlling the motion and the shape of Bose–Einstein condensates.