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arXiv · 2509.09783

Pseudogap-induced change in the nature of the Lifshitz transition in the two-dimensional Hubbard model

Maria C. O. Aguiar·Helena Bragança·Indranil Paul·Marcello Civelli
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Abstract

We study the behavior of the density of states and the $B_{1g}$ nematic susceptibility extracted from Raman response data across the doping-driven Lifshitz transition comparing the weak and strong interaction cases. Our results were obtained using cluster dynamical mean field theory for the two-dimensional Hubbard model. In the weakly correlated Fermi liquid regime, both quantities are approximately symmetric around the Lifshitz transition doping $p_{LT}$. In the strongly correlated regime, the low-doping pseudogap leads to an asymmetric, discontinuous evolution when the Fermi surface changes from hole-like to electron-like at $p_{LT}$. The Lifshitz transition thus changes character because it is tied to the pseudogap-Fermi-liquid transition. These results are consistent with available observations and should foster further experimental investigations.

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Maria C. O. Aguiar, Helena Bragança, Indranil Paul, Marcello Civelli. 2025-09-11. Pseudogap-induced change in the nature of the Lifshitz transition in the two-dimensional Hubbard model. https://doi.org/10.1007/s13538-025-01958-9

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