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arXiv · 2512.04602

Ab initio study of Coulomb drag driven electron-hole bifluidity in doped graphene

Dwaipayan Paul·Elena Trukhan·Nakib H. Protik
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Abstract

Motivated by the notion that a preponderance of Coulomb interactions might lead to hydrodynamics, we carry out an ab initio calculation of the charge carrier transport properties of the electron-hole plasma of doped graphene. We include both the phonon and Coulomb interactions within a momentum and band resolved Boltzmann transport formalism. We find that, under suitable conditions, the strong Coulomb drag effect induces effects like negative conductivity and joint electron-hole hydrodynamics (bifluidity) in the plasma. We also identify the exclusive electron or hole hydrodynamics. We find that there is a strong violation of the Wiedemann-Franz law in the low doped regimes. Our work elucidates the roles of the microscopic scattering mechanisms that drive these hydrodynamic phenomena.

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Dwaipayan Paul, Elena Trukhan, Nakib H. Protik. 2025-12-04. Ab initio study of Coulomb drag driven electron-hole bifluidity in doped graphene. https://arxiv.org/abs/2512.04602

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