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arXiv · 2407.02270

Strange metal at the Lifshitz transition

Yi-Hui Xing·Wu-Ming Liu·Xiao-Tian Zhang
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Abstract

Strange metal behavior is widely observed in cuprates, ruthenates, and twisted bilayer graphene. We study quantum critical transport at a two-dimensional Lifshitz transition, where the Fermi surface hosts a van Hove singularity and changes from convex to concave. Self-consistently solving the fermion-boson coupled system, we demonstrate a linear-in-$1/\omega$ optical conductivity driven by the interplay between impurity and critical scattering. The resistivity exhibits a persistent linear-in-$T$ in the quantum critical regime down to $T\rightarrow 0$. Spatially fluctuating Yukawa interaction further extends the linear-in-$T$ regime, providing a unified mechanism for strange metallic transport at the Lifshitz transition.

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Yi-Hui Xing, Wu-Ming Liu, Xiao-Tian Zhang. 2024-07-02. Strange metal at the Lifshitz transition. https://doi.org/10.1007/s11433-026-3106-6

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