title: Resonant control of elastic collisions in an optically trapped fermi gas of atoms.
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+/-1.4 G and has a width of 8.0+/-1.1 G. Using this resonance, we have changed the elastic collision cross section in the gas by nearly 3 orders of magnitude.
authors: JILA, National Institute of Standards and Technology, University of Colorado, Boulder, Colorado 80309, USA.
authors: T
authors: T
authors: Loftus
authors: C A
authors: CA
authors: Regal
authors: C
authors: C
authors: Ticknor
authors: J L
authors: JL
authors: Bohn
authors: D S
authors: DS
authors: Jin