arXiv:cond-mat/0507435 · Journal of Physics B Atomic Molecular and Optical Physics

A permanent magnetic film atom chip for Bose–Einstein condensation

B V Hall, S. Whitlock, F Scharnberg, P Hannaford, A Sidorov

Published Dec 5, 2005• 33 citations

Abstract

We present a hybrid atom chip which combines a permanent magnetic film with a micromachined current-carrying structure used to realize a Bose–Einstein condensate (BEC). A novel TbGdFeCo material with large perpendicular magnetization has been tailored to allow small scale, stable magnetic potentials for ultracold atoms. We are able to produce 87 Rb BEC in a magnetic trap based on either the permanent magnetic film or the current-carrying structure. Using the condensate as a magnetic field probe we perform cold atom magnetometry to profile both the field magnitude and gradient as a function of distance from the magnetic film surface. Finally, we discuss future directions for our permanent magnetic film atom chip.

DOI: 10.1088/0953-4075/39/1/004

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