Observation of Resonance Condensation of Fermionic Atom Pairs

2004/01/27 by C. A. Regal, Markus Greiner, M. Greiner +1 · 1 voice · 21 citations
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Quantum, superfluid, helium dynamics #cond-mat.stat-mech

paper · pdf · doi:10.1103/physrevlett.92.040403

openalex publication_date 2004/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We have observed condensation of fermionic atom pairs in the BCS-BEC crossover regime. A trapped gas of fermionic 40K atoms is evaporatively cooled to quantum degeneracy and then a magnetic-field Feshbach resonance is used to control the atom-atom interactions. The location of this resonance is precisely determined from low-density measurements of molecule dissociation. In order to search for condensation on either side of the resonance, we introduce a technique that pairwise projects fermionic atoms onto molecules; this enables us to measure the momentum distribution of fermionic atom pairs. The transition to condensation of fermionic atom pairs is mapped out as a function of the initial atom gas temperature T compared to the Fermi temperature T(F) for magnetic-field detunings on both the BCS and BEC sides of the resonance.

Cited by

• BCS pairing in Fermi systems withNdifferent hyperfine states
• Vortices and superfluidity in a strongly interacting Fermi gas
• Ultracold Two-Component Fermionic Gases with a Magnetic Field Gradient Near a Feshbach Resonance
• Nonequilibrium Dynamics and Thermodynamics of a Degenerate Fermi Gas Across a Feshbach Resonance
• The Bose-Einstein Condensate of G-wave Molecules and Its Intrinsic Angular Momentum
• Impact of Disorder on the Superconducting Properties and BCS-BEC Crossover in FeSe Single Crystals
• Heating and atom loss during upward ramps of Feshbach resonance levels in Bose-Einstein condensates
• Weighted Hartree-Fock-Bogoliubov method for interacting fermions: An application to ultracold Fermi superfluids
• Quantum Atom Optics: Theory and Applications to Quantum Technology
• Atomic thermometry in optical lattice clocks
• Unconventional color superfluidity in ultra-cold fermions: Quintuplet\n pairing, quintuple point and pentacriticality
• Cold Atoms in Driven Optical Lattices
• High-Temperature Atomic Superfluidity in Lattice Bose-Fermi Mixtures
• Anisotropic Fermi Superfluid viap-Wave Feshbach Resonance
• Molecular regimes in ultracold Fermi gases
• Comparison between a diagrammatic theory for the BCS-BEC crossover and quantum Monte Carlo results
• Josephson effects in an interaction-asymmetric junction across the BCS-BEC crossover
• Bose-Einstein condensation of trapped interacting spin-1 atoms
• Collective Excitations of a Degenerate Gas at the BEC-BCS Crossover
• Limits on Universality in Ultracold Three-Boson Recombination
• Bose-Einstein Condensation of Particle-Hole Pairs in Ultracold Fermionic Atoms Trapped within Optical Lattices
• Formation of ultracold ³⁹K¹³³Cs Feshbach molecules
• Bose–Einstein condensate [wikipedia]

Discussions

• One version of superconductivity is that of "pre-formed pairs" where a pair of fermions combine to form a new particle which has integer spin and which then Bose-condenses. The Bose condensate can be [stackexchange, 5 points]

Related

• Experimental realization of BCS-BEC crossover physics with a Fermi gas of atoms
• A molecular Bose-Einstein condensate emerges from a Fermi sea
• Observation of Bose-Einstein Condensation of Molecules
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• Inter-Condensate Tunneling in Bose-Einstein Condensates with Feshbach Resonances