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arXiv · 2407.21102

Enhanced Strange Metallicity due to Hubbard-U Coulomb Repulsion

Andrew Hardy·Olivier Parcollet·Antoine Georges·Aavishkar A. Patel
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Abstract

We solve a model of electrons with Hubbard-$U$ Coulomb repulsion and a random Yukawa coupling to a two-dimensional bosonic bath, using an extended dynamical mean field theory scheme. Our model exhibits a quantum critical point, at which the repulsive component of the electron interactions strongly enhances the effects of the quantum critical bosonic fluctuations on the electrons, leading to a breakdown of Fermi liquid physics and the formation of a strange metal with `Planckian' ($\mathcal{O}(k_B T/\hbar)$) quasiparticle decay rates at low temperatures $T\rightarrow 0$. Furthermore, the eventual Mott transition that occurs as the repulsion is increased seemingly bounds the maximum decay rate in the strange metal. Our results provide insight into low-temperature strange metallicity observed in proximity to a Mott transition, as is observed, for instance, in recent experiments on certain moir\'{e} materials.

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Andrew Hardy, Olivier Parcollet, Antoine Georges, Aavishkar A. Patel. 2024-07-30. Enhanced Strange Metallicity due to Hubbard-U Coulomb Repulsion. https://doi.org/10.1103/physrevlett.134.036502

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