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arXiv · 2205.14175

Kinetic theory of {\it tilted} Dirac cone materials

A. Moradpouri·Mahdi Torabian·S. A. Jafari
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Abstract

We formulate the Boltzmann kinetic equations for interacting tilted Dirac fermions in two space dimensions characterized by a tilt parameter $0\leζ<1$. Solving the linearized Boltzmann equation, we find that the broadening of the Drude pole is enhanced by $κ(ζ)\times(1-ζ^2)^{-1/2}$, where the $κ$ is interaction-induced enhancement factor. The intensity of the Drude pole is also anisotropically enhanced by $(1-ζ^2)^{-1}$. The ubiquitous "redshift" factors $(1-ζ^2)^{1/2}$ can be regarded as a manifestation of an underlying spacetime structure in such solids. The additional broadening $κ$ indicates that interaction effects are more pronounced for electrons in a $ζ$-deformed Minkowski spacetime of tilted Dirac fermions.

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A. Moradpouri, Mahdi Torabian, S. A. Jafari. 2023-05-30. Kinetic theory of {\it tilted} Dirac cone materials. https://arxiv.org/abs/2205.14175

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