Critical strange metal from fluctuating gauge fields in a solvable random model

Building upon techniques employed in the construction of the Sachdev-Ye-Kitaev model, which is a solvable (0 + 1)-dimensional model of a non-Fermi liquid, we develop a solvable infinite-ranged random-hopping model of fermions coupled to fluctuating $U(1)$ gauge fields. In a specific large-N limit, our model realizes a gapless non-Fermi-liquid phase, which combines the effects of hopping and interaction terms. We derive the thermodynamic properties of the non-Fermi-liquid phase realized by this model and the charge transport properties of an infinite-dimensional version with spatial structure.