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Measurement of P-Wave Threshold Law Using Evaporatively Cooled Fermionic Atoms



B. L. DeMarco, J L. Bohn, J P. Burke, M J. Holland, Deborah S. Jin


We have measured independently both s-wave and p-wave cross-dimensional thermalization rates for ultracold 40K atoms held in a magnetic trap. These measurements reveal that this fermionic isotope has a large positive s-wave triplet scattering length in addition to a low temperature p-wave shape resonance. We have measured directly the p-wave threshold law which, combined with the Fermi statistics, dramatically suppresses elastic collision rates at low temperatures. In addition, we present initial evaporative cooling results that make possible these collision measurements and are a precursor to achieving quantum degeneracy in this neutral, low-density Fermi system.
Physical Review Letters
No. 21


atom trapping and cooling, fermions, potassium


DeMarco, B. , Bohn, J. , Burke, J. , Holland, M. and Jin, D. (1999), Measurement of P-Wave Threshold Law Using Evaporatively Cooled Fermionic Atoms, Physical Review Letters (Accessed April 14, 2024)
Created April 30, 1999, Updated October 12, 2021