End-point thermodynamics of an atomic Fermi gas subject to a Feshbach resonance
- JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309-0440 (United States)
The entropy and kinetic, potential, and interaction energies of an atomic Fermi gas in a trap are studied under the assumption of thermal equilibrium for finite temperature. A Feshbach resonance can cause the fermions to pair into diatomic molecules. The entropy and energies of mixtures of such molecules with unpaired atoms are calculated, in relation to recent experiments on molecular Bose-Einstein condensates produced in this manner. It is shown that, starting with a Fermi gas of temperature T=0.1T{sub F}{sup 0}, where T{sub F}{sup 0} is the noninteracting Fermi temperature, an extremely cold degenerate Fermi gas of temperature T < or approx. 0.01T{sub F}{sup 0} may be produced without further evaporative cooling. This requires adiabatic passage of the resonance, subsequent sudden removal of unpaired atoms, and adiabatic return. We also calculate the ratio of the interaction energy to the kinetic energy, a straightforward experimental signal which may be used to determine the temperature of the atoms and indicate condensation of the molecules.
- OSTI ID:
- 20646403
- Journal Information:
- Physical Review. A, Vol. 70, Issue 4; Other Information: DOI: 10.1103/PhysRevA.70.043609; (c) 2004 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
Similar Records
Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region
Superfluid transition temperature in a trapped gas of Fermi atoms with a Feshbach resonance