Spin Transport in Cold Fermi gases: A Pseudogap Interpretation of Spin Diffusion Experiments at Unitarity

Abstract

We address recent spin transport experiments in ultracold unitary Fermi gases. We provide a theoretical understanding for how the measured temperature dependence of the spin diffusivity at low $T$ can disagree with the expected behavior of a Fermi liquid (FL) while the spin susceptiblity(following the experimental protocols) is consistent with a Fermi liquid picture. We show that the experimental protocols for extracting ${\chi }_s$ are based on a FL presumption; relaxing this leads to consistency within (but not proof of) a pseudogap-based approach. Our tranport calculations yield insight into the measured strong suppression of the spin diffusion constant at lower $T$.

4 pages, 2 figures

References in corpus (6)

• Using photoemission spectroscopy to probe a strongly interacting Fermi gas
• Universal Quantum Viscosity in a Unitary Fermi Gas
• Universal Spin Transport in a Strongly Interacting Fermi Gas
• Shear viscosity and damping for a Fermi gas in the unitarity limit
• Spin diffusion in Fermi gases
• Transport implications of Fermi arcs in the pseudogap phase of the cuprates

Cited by in corpus (16)

• Observation of a pairing pseudogap in a two-dimensional Fermi gas
• Transverse Demagnetization Dynamics of a Unitary Fermi Gas
• Universal spin dynamics in two-dimensional Fermi gases
• Breakdown of Fermi liquid description for strongly interacting fermions
• Quantum mechanical limitations to spin diffusion in the unitary Fermi gas
• Observation of quantum-limited spin transport in strongly interacting two-dimensional Fermi gases
• Cooper pairing above the critical temperature in a unitary Fermi gas
• Pseudogaps in strongly interacting Fermi gases
• Observation of the Leggett-Rice effect in a unitary Fermi gas
• Density and spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime
• Universal Spin Transport and Quantum Bounds for Unitary Fermions
• Pairing correlations across the superfluid phase transition in the unitary Fermi gas
• The temperature evolution of the shear viscosity in a unitary Fermi gas
• Probing strongly interacting atomic gases with energetic atoms
• Collisionless spin dynamics in a magnetic field gradient
• Crossover from collisionless to collisional spin dynamics of polarized fermions