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arXiv · 2310.03653

Interacting nodal semimetals with non-linear bands

Arianna Poli·Niklas Wagner·Max Fischer·Alessandro Toschi·Giorgio Sangiovanni·Sergio Ciuchi
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Abstract

We investigate the quasi-particle and transport properties of a model describing interacting Dirac and Weyl semimetals in the presence of local Hubbard repulsion $U$, where we explicitly include a deviation from the linearity of the energy-momentum dispersion through an intermediate-energy scale $\Lambda$. Our focus lies on the correlated phase of the semimetal. At the nodal point, the renormalization of spectral weight at a fixed temperature $T$ exhibits a weak dependence on $\Lambda$ but is sensitive to the proximity to the Mott transition. Conversely, the scattering rate of quasi-particles and the resistivity display high-temperature exponents that crucially rely on $\Lambda$, leading to a crossover towards a conventional Fermi-liquid behaviour at finite T. Finally, by employing the Nernst-Einstein relation for conductivity, we identify a corresponding density crossover as a function of the chemical potential.

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Arianna Poli, Niklas Wagner, Max Fischer, Alessandro Toschi, Giorgio Sangiovanni, Sergio Ciuchi. 2023-10-05. Interacting nodal semimetals with non-linear bands. https://doi.org/10.1103/physrevb.109.045118

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