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Resonant control of elastic collisions in an optically trapped Fermi gas of atoms

T. Loftus·C. A. Regal·C. Ticknor·J. L. Bohn·D. S. Jin
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Abstract

We have loaded an ultracold gas of fermionic atoms into a far off resonance optical dipole trap and precisely controlled the spin composition of the trapped gas. We have measured a magnetic-field Feshbach resonance between atoms in the two lowest energy spin-states, |9/2, -9/2> and |9/2, -7/2>. The resonance peaks at a magnetic field of 201.5 plus or minus 1.4 G and has a width of 8.0 plus or minus 1.1 G. Using this resonance we have changed the elastic collision cross section in the gas by nearly 3 orders of magnitude.

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T. Loftus, C. A. Regal, C. Ticknor, J. L. Bohn, D. S. Jin. 2001-11-29. Resonant control of elastic collisions in an optically trapped Fermi gas of atoms. https://doi.org/10.1103/physrevlett.88.173201

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