Macroscopic magnetic guide for cold atoms

We demonstrate a macroscopic magnetic guide for cold atoms with suppressed longitudinal field curvature which is highly desired for atom interferometry. The guide is based on macroscopic copper tape coils in a copropagating currents geometry, where the atoms are located between the coils few cm away from each surface. The symmetric geometry provides a much lower magnetic field curvature per fixed length that promises longer coherence time for atom interferometers. A double-tape design of each coil allows a smooth translation of guided atoms without addition of an external bias field. The guide is also immune from the current and thermal noise by virtue of the turns averaging and a large working distance, respectively. We present the experimental results of guide application to atom interferometry.