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Trapping Fermionic $^{40}$K and Bosonic $^{87}$Rb on a Chip

S. Aubin·M. H. T. Extavour·S. Myrskog·L. J. LeBlanc·J. Esteve·S. Singh·P. Scrutton·D. McKay·R. McKenzie·I. D. Leroux·A. Stummer·J. H. Thywissen
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Abstract

We demonstrate the loading of a Bose-Fermi mixture into a microfabricated magnetic trap. In a single-chamber vacuum system, laser-cooled atoms are transported to the surface of a substrate on which gold wires have been microfabricated. The magnetic field minimum formed near these current-carrying wires is used to confine up to $6\times10^4$ neutral $^{40}$K atoms. In addition, we can simultaneously load $2 \times 10^5$ $^{87}$Rb atoms, demonstrating the confinement of two distinct elements with such a trap. In a sequence optimized for $^{87}$Rb alone, we observe up to $1 \times 10^7$ trapped atoms. We describe in detail the experimental apparatus, and discuss prospects for evaporative cooling towards quantum degeneracy in both species.

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S. Aubin, M. H. T. Extavour, S. Myrskog, L. J. LeBlanc, J. Esteve, S. Singh, P. Scrutton, D. McKay, R. McKenzie, I. D. Leroux, A. Stummer, J. H. Thywissen. 2005-08-05. Trapping Fermionic $^{40}$K and Bosonic $^{87}$Rb on a Chip. https://doi.org/10.1007/s10909-005-7322-5

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