Eur. Phys. J. D 32, 171-180 (2005)
https://doi.org/10.1140/epjd/e2005-00016-x

Atom chips in the real world: the effects of wire corrugation

¹ Laboratoire Charles Fabry de l'Institut d'Optique, UMR 8501 du CNRS, 91403 Orsay Cedex, France
² Laboratoire de Photonique et de Nanostructures, UPR 20 du CNRS, 91460 Marcoussis, France

Corresponding author: ^a thorsten.schumm@iota.u-psud.fr

Received: 16 July 2004
Revised: 28 October 2004
Published online: 1 February 2005

Abstract

We present a detailed model describing the effects of wire corrugation on the trapping potential experienced by a cloud of atoms above a current carrying micro wire. We calculate the distortion of the current distribution due to corrugation and then derive the corresponding roughness in the magnetic field above the wire. Scaling laws are derived for the roughness as a function of height above a ribbon shaped wire. We also present experimental data on micro wire traps using cold atoms which complement some previously published measurements [CITE] and which demonstrate that wire corrugation can satisfactorily explain our observations of atom cloud fragmentation above electroplated gold wires. Finally, we present measurements of the corrugation of new wires fabricated by electron beam lithography and evaporation of gold. These wires appear to be substantially smoother than electroplated wires.