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arXiv · 2403.00062

Strong non-linear response of strange metals

Serhii Kryhin·Subir Sachdev·Pavel A. Volkov
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Abstract

We show that nonlinear transport responses in strange metals are strong, larger by a factor of $E_F/T$ than in Fermi liquids. Within the two-dimensional Yukawa-Sachdev-Ye-Kitaev model of a Fermi surface with a spatially random coupling to a critical scalar, the third order conductivity is found to diverge as $1/T$ at low $T$, indicating the existence of a voltage-temperature scaling regime in the conductance. Its frequency and orientation dependence contains information on relaxation times of heat and electron distribution deformations, providing a new set of tools to characterize strange metals.

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Serhii Kryhin, Subir Sachdev, Pavel A. Volkov. 2024-02-29. Strong non-linear response of strange metals. https://doi.org/10.1103/4jxd-z3pm

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