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arXiv · 2012.06159

Strange Metal Solution in the Diagrammatic Theory for the $2d$ Hubbard Model

Aaram J. Kim·Philipp Werner·Evgeny Kozik
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Abstract

We show that the numerically exact bold-line diagrammatic theory for the $2d$ Hubbard model exhibits a non-Fermi-liquid (NFL) strange metal state, which is connected to the SYK NFL in the strong-interaction limit. The solution for the doped system features the expected phenomenology with the NFL near half-filling at strong couplings and in a wide temperature range enclosed by the atomic state at high temperatures and a Fermi liquid at low temperatures. We demonstrate, however, that this behavior in the weakly doped regime is due to the unphysical branch of the Luttinger-Ward functional. On the other hand, our analysis shows that the NFL physics is realized at larger doping.

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Aaram J. Kim, Philipp Werner, Evgeny Kozik. 2020-12-11. Strange Metal Solution in the Diagrammatic Theory for the $2d$ Hubbard Model. https://arxiv.org/abs/2012.06159

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