Potential Energy of aK<mml:mprescripts/><mml:none/>40Fermi Gas in the BCS-BEC Crossover

2006/07/31 by J. T. Stewart, John T. Stewart, John Gaebler +3
Physics and Astronomy · #Atomic physics #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Electron #Energy (signal processing) #Fermi gas #Feshbach resonance #Molecule #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum mechanics #Quantum, superfluid, helium dynamics #Ultracold atom #Unitarity #Universality (dynamical systems) #cond-mat.other

paper · pdf · doi:10.1103/physrevlett.97.220406

published as Phys.Rev.Lett.97:220406,2006

openalex publication_date 2006/11/30 · arxiv created 2007/01/11 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06

Abstract

We present a measurement of the potential energy of an ultracold trapped gas of 40K atoms in the BCS-BEC crossover and investigate the temperature dependence of this energy at a wide Feshbach resonance, where the gas is in the unitarity limit. In particular, we study the ratio of the potential energy in the region of the unitarity limit to that of a noninteracting gas, and in the T=0 limit we extract the universal many-body parameter beta. We find beta=-0.54_-0.12;+0.05; this value is consistent with previous measurements using 6Li atoms and also with recent theory and Monte Carlo calculations. This result demonstrates the universality of ultracold Fermi gases in the strongly interacting regime.

Citations

• Feshbach-Resonant Interactions inK<mml:mprescripts/><mml:none/>40andLi<mml:mprescripts/><mml:none/>6Degenerate Fermi Gases
• Superfluidity of Spin-Polarized6Li
• Critical Temperature and Thermodynamics of Attractive Fermions at Unitarity
• Observation of resonance condensation of fermionic atom pairs
• Momentum Distribution of a Fermi Gas of Atoms in the BCS-BEC Crossover
• Vortices and superfluidity in a strongly interacting Fermi gas
• Mechanical stability of a strongly interacting Fermi gas of atoms
• Observation of Fermi Pressure in a Gas of Trapped Atoms
• Broad vs. narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atoms
• Quantitative Comparison between Theoretical Predictions and Experimental Results for the BCS-BEC Crossover
• Equation of state of a superfluid Fermi gas in the BCS-BEC crossover