The Equation of State of a Low-Temperature Fermi Gas with Tunable Interactions

Abstract

Interacting fermions are ubiquitous in nature and understanding their thermodynamics is an important problem. We measure the equation of state of a two-component ultracold Fermi gas for a wide range of interaction strengths at low temperature. A detailed comparison with theories including Monte-Carlo calculations and the Lee-Huang-Yang corrections for low-density bosonic and fermionic superfluids is presented. The low-temperature phase diagram of the spin imbalanced gas reveals Fermi liquid behavior of the partially polarized normal phase for all but the weakest interactions. Our results provide a benchmark for many-body theories and are relevant to other fermionic systems such as the crust of neutron stars.

28 pages, 7 figures

References in corpus (17)

• Observation of Fermi Polarons in a Tunable Fermi Liquid of Ultracold Atoms
• Observation of Phase Separation in a Strongly-Interacting Imbalanced Fermi Gas
• Thermodynamics of the BCS-BEC crossover
• Phase diagram of a two-component Fermi gas with resonant interactions
• Fermi-Polaron: Diagrammatic Monte Carlo for Divergent Sign-Alternating Series
• Deformation of a Trapped Fermi Gas with Unequal Spin Populations
• Normal state of a polarized Fermi gas at unitarity
• Precision Measurements of Collective Oscillations in the BEC-BCS Crossover
• Quantum Fluctuations in the Superfluid State of the BCS-BEC Crossover
• Determination of the Superfluid Gap in Atomic Fermi Gases by Quasiparticle Spectroscopy
• Equation of state of a superfluid Fermi gas in the BCS-BEC crossover
• Quantum Monte Carlo Simulations of the BCS-BEC Crossover at Finite Temperature
• Realization of a strongly interacting Bose-Fermi mixture from a two-component Fermi gas
• Three-boson problem at low energy and Implications for dilute Bose-Einstein condensates
• Determination of the Equation of State of a Two-Component Fermi Gas at Unitarity
• Pair correlations of an expanding superfluid Fermi gas
• Superfluid equation of state of dilute composite bosons

Cited by in corpus (41)

• Quantum-fluctuation-driven crossover from a dilute Bose-Einstein condensate to a macro-droplet in a dipolar quantum fluid
• Repulsive Fermi polarons in a resonant mixture of ultracold ${}^6$Li atoms
• Homogeneous Atomic Fermi Gases
• Time dependent impurity in ultracold fermions: orthogonality catastrophe and beyond
• Ultra-cold Polarized Fermi Gases
• Cooling in strongly correlated optical lattices: prospects and challenges
• Measurement of the Homogeneous Contact of a Unitary Fermi gas
• Precise determination of the structure factor and contact in a unitary Fermi gas
• Resonantly Interacting Fermions In a Box
• Breakdown of Fermi liquid description for strongly interacting fermions
• BEC-BCS crossover and universal relations in unitary Fermi gases
• Quantum Monte Carlo approaches to nuclear and atomic physics
• Ultracold atoms and the Functional Renormalization Group
• Universal properties of Fermi gases in arbitrary dimensions
• Universal contact of strongly interacting fermions at finite temperatures
• Spin diffusion in Fermi gases
• Strongly correlated Bose gases
• Connecting few-body inelastic decay to many-body correlations: a weakly coupled impurity in a resonant Fermi gas
• Polylogs, thermodynamics and scaling functions of one-dimensional quantum many-body systems
• Quantitative comparison between theoretical predictions and experimental results for Bragg spectroscopy of a strongly interacting Fermi superfluid
• Calibration of Interaction Energy between Bose and Fermi Superfluids
• Universality of the unitary Fermi gas: A few-body perspective
• Critical behaviours of contact near phase transitions
• Predicting Energies of Small Clusters from the Inhomogeneous Unitary Fermi Gas
• Imaginary polarization as a way to surmount the sign problem in ab initio calculations of spin-imbalanced Fermi gases
• Virial expansion coefficients in the harmonic approximation
• Effective-range dependence of resonant Fermi gases
• Heat and spin transport in a cold atomic Fermi gas
• Tan contact and universal high momentum behavior of the fermion propagator in the BCS-BEC crossover
• Hetero pairing and component-dependent pseudogap phenomena in an ultracold Fermi gas with mass imbalance
• Sarma phase in relativistic and non-relativistic systems
• Analytical thermodynamics of a strongly attractive three-component Fermi gas in one dimension
• Occupation numbers of the harmonically trapped few-boson system
• Exact results for polaron and molecule in one-dimensional spin-1/2 Fermi gas
• Quantum oscillations in ultracold Fermi gases : realizations with rotating gases or artificial gauge fields
• SU(N) Fermi liquid at finite temperature
• Error estimates and specification parameters for functional renormalization
• The self-energy of an impurity in an ideal Fermi gas to second order in the interaction strength
• Dynamic structure factor of a strongly correlated Fermi superfluid within a density functional theory approach
• Spin-polarized low-density neutron matter
• Universal Relations for Fermions with Large Scattering Length