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arXiv · 2505.06479

Microscopic lattice model for quartic semi-Dirac fermions in two dimensions

Mohamed M. Elsayed·Valeri N. Kotov
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Abstract

We propose a lattice model for the realization of exotic quartic semi-Dirac fermions, i.e. quasiparticles exhibiting a dispersion with quartic momentum dependence in a given direction, and a linear dependence in the perpendicular direction. A tight binding model is employed, allowing for hopping between up to fourth nearest neighbors and anisotropic hopping parameters. In addition, we introduce short range electron-electron interactions which are necessary to stabilize the quartic semi-Dirac phase. Without interactions, or in the presence of long range correlations, the lattice is unstable towards formation of either anisotropic Dirac cones, or simple (quadratic) semi-Dirac phase.

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Mohamed M. Elsayed, Valeri N. Kotov. 2025-05-10. Microscopic lattice model for quartic semi-Dirac fermions in two dimensions. https://doi.org/10.1088/1361-648x%2Fadf0d4

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