Establishing the Presence of Coherence in Atomic Fermi Superfluids: Spin-Flip and Spin-Preserving Bragg Scattering at Finite Temperatures

Abstract

We show how the difference between the finite temperature T structure factors, called S_-, associated with spin and density, can be used as a indication of superfluidity in ultracold Fermi gases. This observation can be exploited in two photon Bragg scattering experiments on gases which undergo BCS- Bose Einstein condensation crossover. Essential to our calculations is a proper incorporation of spin and particle number conservation laws which lead to compatibility at general T with two f-sum rules. Because it is applicable to general scattering lengths, a measurement of S- can be a useful, direct approach for establishing where superfluidity occurs.

References in corpus (6)

• Vortices and Superfluidity in a Strongly Interacting Fermi Gas
• Exploring the Thermodynamics of a Universal Fermi Gas
• Universal behavior of pair correlations in a strongly interacting Fermi gas
• Bragg spectroscopy of a strongly interacting Fermi gas
• Critical Temperature and Condensate Fraction of a Fermion Pair Condensate
• Bragg Spectroscopy of Cold Atomic Fermi Gases

Cited by in corpus (28)

• Tunable Superfluidity and Quantum Magnetism with Ultracold Polar Molecules
• Realizing Fractional Chern Insulators with Dipolar Spins
• Virial expansion for a strongly correlated Fermi system and its application to ultracold atomic Fermi gases
• Pseudogaps in strongly interacting Fermi gases
• Dynamic spin response of a strongly interacting Fermi gas
• Microscopic Approach to Shear Viscosities in Superfluid Gases: From BCS to BEC
• Pseudogap phenomena in ultracold atomic Fermi gases
• Perfect Fluids and Bad Metals: Transport Analogies Between Ultracold Fermi Gases and High $T_c$ Superconductors
• Quantitative comparison between theoretical predictions and experimental results for Bragg spectroscopy of a strongly interacting Fermi superfluid
• Theories of Linear Response in BCS Superfluids and How They Meet Fundamental Constraints
• Universal dynamic structure factor of a strongly correlated Fermi gas
• Low-momentum dynamic structure factor of a strongly interacting Fermi gas at finite temperature: The Goldstone phonon and its Landau damping
• Spin Transport in Cold Fermi gases: A Pseudogap Interpretation of Spin Diffusion Experiments at Unitarity
• The Compressibility in Strongly Correlated Superconductors and Superfluids: From BCS to BEC
• Signatures of pairing and spin-orbit coupling in correlation functions of Fermi gases
• Conductivity in Pseudogapped Superconductors: The Role of the Fermi Arcs
• Dynamic structure factor of a strongly correlated Fermi superfluid within a density functional theory approach
• The Two Component Optical Conductivity in the Cuprates: A Necessary Consequence of Preformed Pairs
• Spin-dependent Bragg spectroscopy of a spinor Bose gas
• Gauge Invariant Linear Response Theory of Relativistic BCS superfluids
• Theory of THz Conductivity in the Pseudogap Phase of the Cuprates: A Pre-Formed Pair Perspective
• Response function of strongly interacting Fermi gas in a virial expansion
• Relation connecting thermodynamics and transport of atomic unitary Fermi superfluids
• Density and Spin Linear Response of Atomic Fermi Superfluids with Population Imbalance in BCS-BEC Crossover
• Establishing the Gauge Invariant Linear Response of Fermionic Superfluids with Pair Fluctuations: A Diagrammatic approach
• Comment on "Density and Spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime"
• Theory of Diamagnetism in the Pseudogap Phase: Implications from the Self energy of Angle Resolved Photoemission
• Fluctuation conductivity due to the preformed local pairs