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arXiv · 2304.12221

Coulomb drag and heat transfer in strange metals

A. L. Chudnovskiy·Alex Levchenko·Alex Kamenev
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Abstract

We address Coulomb drag and near-field heat transfer in a double-layer system of incoherent metals. Each layer is modeled by an array of tunnel-coupled SYK dots with random inter-layer interactions. Depending on the strength of intra-dot interactions and inter-dot tunneling, this model captures the crossover from the Fermi liquid to a strange metal phase. The absence of quasiparticles in the strange metal leads to temperature-independent drag resistivity, which is in strong contrast with the quadratic temperature dependence in the Fermi liquid regime. We show that all the parameters can be independently measured in near-field heat transfer experiments, performed in Fermi liquid and strange metal regimes.

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A. L. Chudnovskiy, Alex Levchenko, Alex Kamenev. 2023-04-24. Coulomb drag and heat transfer in strange metals. https://doi.org/10.1103/physrevlett.131.096501

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