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A permanent magnetic film atom chip for Bose-Einstein condensation

B. V. Hall·S. Whitlock·F. Scharnberg·P. Hannaford·A. Sidorov
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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. 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 87Rb Bose-Einstein condensates 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.

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B. V. Hall, S. Whitlock, F. Scharnberg, P. Hannaford, A. Sidorov. 2005-07-19. A permanent magnetic film atom chip for Bose-Einstein condensation. https://doi.org/10.1088/0953-4075%2F39%2F1%2F004

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