'Atom chips' are miniaturized devices where quantum degenerate gases can be trapped. These ultracold atoms have temperatures below 1uK and are hovering a few um above a solid surface. Atom chips can be useful for high-precision measurements (atom interferometers) or for the study of low-dimensional coherent matter waves.

• We are interested in the perturbation of a cold atom by the thermal field coming from the solid surface. This radiation is much more intense than blackbody radiation and it induces, for example, spin flips and decoherence of the quantum state of the trapped atom. These processes can be measured from the trap loss and they set limits for coherent atom interferometry, for example.
• We have recently performed analytical and numerical calculations of magnetic fields near a metallic layer and a finite size wire. (Link to the paper.)
• Previously, we compared our theory with a measurement of the trap lifetime performed in the group of Jörg Schmiedmayer. (Link to the paper.)

Cooperations:

• Ron Folman (Ben Gurion University, Beer Sheva, Israel)
• Jörg Schmiedmayer (Vienna, Austria)

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C. Henkel, 23 Jan 2008