The potential energy of a ${}^{40}$K Fermi gas in the BCS-BEC crossover

Abstract

We present a measurement of the potential energy of an ultracold trapped gas of ${}^{40}$K 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 non-interacting 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 ${}^6$Li atoms and also with recent theory and Monte Carlo calculations. This result demonstrates the universality of ultracold Fermi gases in the strongly interacting regime.

References in corpus (8)

• Vortices and Superfluidity in a Strongly Interacting Fermi Gas
• Observation of the Pairing Gap in a Strongly Interacting Fermi Gas
• Crossover from a molecular Bose-Einstein condensate to a degenerate Fermi gas
• Critical Temperature and Thermodynamics of Attractive Fermions at Unitarity
• Equation of state of a superfluid Fermi gas in the BCS-BEC crossover
• Temperature of a trapped unitary Fermi gas at finite entropy
• Broad versus narrow Fano-Feshbach resonances in the BCS-BEC crossover with trapped Fermi atom
• Feshbach-Resonant Interactions in 40K and 6Li Degenerate Fermi Gases

Cited by in corpus (34)

• Many-Body Physics with Ultracold Gases
• Theory of ultracold Fermi gases
• Gravity duals for non-relativistic CFTs
• Using photoemission spectroscopy to probe a strongly interacting Fermi gas
• Bragg spectroscopy of a strongly interacting Fermi gas
• Number of closed-channel molecules in the BEC-BCS crossover
• Virial expansion for a strongly correlated Fermi gas
• Tomographic RF Spectroscopy of a Trapped Fermi Gas at Unitarity
• Measurement of the Entropy and Critical Temperature of a Strongly Interacting Fermi Gas
• Thermodynamic Measurements in a Strongly Interacting Fermi Gas
• Large-N expansion for unitary superfluid Fermi gases
• Three fully polarized fermions close to a p-wave Feshbach resonance
• Finite-Temperature Collective Dynamics of a Fermi Gas in the BEC-BCS Crossover
• Energetics and Structural Properties of Trapped Two-Component Fermi Gases
• Unitary Fermi Gas in a Harmonic Trap
• Virial theorems for trapped cold atoms
• Nonlinear Schrödinger equation for a superfluid Fermi gas from BCS to Bose crossover
• Thermodynamics of a Trapped Unitary Fermi Gas
• The ground state energy at unitarity
• Determination of the Equation of State of a Two-Component Fermi Gas at Unitarity
• Comparative study of strong coupling theories of a trapped Fermi gas at unitarity
• Imbalanced Superfluid Phase of a Trapped Fermi Gas in the BCS-BEC Crossover Regime
• Dilute neutron matter on the lattice at next-to-leading order in chiral effective field theory
• Three fermions in a box at the unitary limit: universality in a lattice model
• Polarized superfluidity in the attractive Hubbard model with population imbalance
• Molecular Bose-Einstein condensation in a versatile low power crossed dipole trap
• Quantum rearrangement and self-consistent BCS-BEC crossover thermodynamics
• Shell-Model Monte Carlo Simulations of BCS-BEC Crossover in Few-Fermion Systems
• Comparative study of the finite-temperature thermodynamics of a unitary Fermi gas
• Ground-state energy of the unitary Fermi gas from the epsilon expansion
• BEC-BCS crossover of a trapped Fermi gas without using the local density approximation
• Universal behavior of a trapped Fermi superfluid in the BCS-unitarity crossover
• Low-momentum ring diagrams of neutron matter at and near the unitary limit
• The virial equation of state for unitary fermion thermodynamics with non-Gaussian correlations