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Pauli Blocking of Collisions in a Quantum Degenerate Atomic Fermi Gas
Published
Author(s)
B. L. DeMarco, S Papp, D S. Jin
Abstract
We have produced an interacting quantum degenerate Fermi gas of atoms composed of two spin-states of magnetically trapped 40K. The relative Fermi energies are adjusted by controlling the populations in each spin-state. Thermodynamic measurements reveal a resulting imbalance in the mean energy per particle between the two species, which is a factor of 1.4 at our lowest temperature. This imbalance of energy comes from a suppression of collisions between atoms in the gas due to the Pauli exclusion principle. Through measurements of the thermal relaxation rate we have directly observed this Pauli blocking as a factor of 2 reduction in the effective collision cross section in the quantum degenerate regime.
Citation
Physical Review Letters
Volume
86
Pub Type
Journals
Keywords
fermi gas, Pauli blocking
Citation
DeMarco, B.
, Papp, S.
and Jin, D.
(2001),
Pauli Blocking of Collisions in a Quantum Degenerate Atomic Fermi Gas, Physical Review Letters
(Accessed October 9, 2025)