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arXiv · 2404.11612

Sublinear transport in Kagome metals: Interplay of Dirac cones and Van Hove singularities

Nikolai Peshcherenko·Ning Mao·Claudia Felser·Yang Zhang
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Abstract

Kagome metals are known to host Dirac fermions and saddle point Van Hove singularities near Fermi level. With the minimal two-pocket model (Dirac cone + Van Hove singularity), we propose a semiclassical theory to explain the experimentally observed sublinear resistivity in Ni$_3$In and other Kagome metals. We derive the full semiclassical description of kinetic phenomena using Boltzmann equation, and demonstrate that internode electron-electron interaction leads to sublinear in $T$ scaling for both electrical and thermal transport at low temperatures. At higher temperatures above the Dirac node chemical potential, thermal and electric current dissipate through distinct scattering channels, making a ground for Wiedemann-Franz law violation.

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Nikolai Peshcherenko, Ning Mao, Claudia Felser, Yang Zhang. 2024-04-17. Sublinear transport in Kagome metals: Interplay of Dirac cones and Van Hove singularities. https://arxiv.org/abs/2404.11612

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