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arXiv · 2103.08607

Planckian Metal at a Doping-Induced Quantum Critical Point

Philipp T. Dumitrescu·Nils Wentzell·Antoine Georges·Olivier Parcollet
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Abstract

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 (SYK) 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.

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Philipp T. Dumitrescu, Nils Wentzell, Antoine Georges, Olivier Parcollet. 2021-03-15. Planckian Metal at a Doping-Induced Quantum Critical Point. https://doi.org/10.1103/physrevb.105.l180404

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