Bad-Metal Relaxation Dynamics in a Fermi Lattice Gas

Abstract

We report the discovery of phenomena consistent with bad-metal relaxation dynamics in the metallic regime of an optical-lattice Hubbard model. The transport lifetime induced by inter-particle scattering for a mass current of atoms excited by stimulated Raman transitions is measured, and the corresponding analog of resistivity is inferred. By exploring a range of temperature, we demonstrate incompatibility with weak-scattering theory and a key characteristic of bad metals: anomalous resistivity scaling consistent with $T$-linear behavior. We also observe the onset of two behaviors---incoherent transport and the approach to the Mott-Ioffe-Regel limit---associated with bad metals. The interaction and temperature scaling of resistivity are verified to be consistent with dynamic mean-field theory (DMFT) predictions of a bad metal, which is associated with the reduction of quasiparticle weight by strong interactions.

see ancillary material for details on methods

References in corpus (7)

• Theory of universal incoherent metallic transport
• Universal Quantum Viscosity in a Unitary Fermi Gas
• Bose-Fermi Mixtures in a Three-dimensional Optical Lattice
• Breakdown of Fermi liquid description for strongly interacting fermions
• Scaling theory of the cuprate strange metals
• Bad-metal behavior reveals Mott quantum criticality in doped Hubbard models
• Transport and Optical Conductivity in the Hubbard Model: A High-Temperature Expansion Perspective

Cited by in corpus (3)

• Bad metallic transport in a cold atom Fermi-Hubbard system
• Spin Transport in a Mott Insulator of Ultracold Fermions
• Quantum simulation of the Hubbard model with ultracold fermions in optical lattices