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Measurement of P-Wave Threshold Law Using Evaporatively Cooled Fermionic Atoms
Published
Author(s)
B. L. DeMarco, J L. Bohn, J P. Burke, M J. Holland, Deborah S. Jin
Abstract
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.
Citation
Physical Review Letters
Volume
82
Issue
No. 21
Pub Type
Journals
Keywords
atom trapping and cooling, fermions, potassium
Citation
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 October 10, 2025)