Planckian metal at a doping-induced quantum critical point

Philipp T. Dumitrescu , Nils Wentzell , Antoine Georges (1, 2) , Olivier Parcollet (3)

1 CPHT - Centre de Physique Théorique [Palaiseau]
2 CdF (institution) - Collège de France
3 IPHT - Institut de Physique Théorique - UMR CNRS 3681

We numerically study a model of interacting spin-$1/2$ electrons with random exchange coupling on a fully connected lattice. This model hosts a quantum critical point separating two distinct metallic phases as a function of doping: a Fermi-liquid phase with a large Fermi-surface volume and a low-doping phase with local moments ordering into a spin glass. We show that this quantum critical point has non-Fermi-liquid properties characterized by $T$-linear Planckian behavior, $\omega /T$ scaling, and slow spin dynamics of the Sachdev-Ye-Kitaev type. The $\omega /T$ scaling function associated with the electronic self-energy is found to have an intrinsic particle-hole asymmetry, a hallmark of a “skewed” non-Fermi liquid.

Domaines: Matière Condensée [cond-mat]

Philipp T. Dumitrescu, Nils Wentzell, Antoine Georges, Olivier Parcollet. Planckian metal at a doping-induced quantum critical point. Physical Review B, 2022, 105 (18), pp.L180404. ⟨10.1103/PhysRevB.105.L180404⟩. ⟨hal-03677048⟩