Extreme electron-hole drag and negative mobility in the Dirac plasma of graphene
Abstract
Coulomb drag between adjacent electron and hole gases has attracted considerable attention, being studied in various two-dimensional systems, including semiconductor and graphene heterostructures. Here we report measurements of electron-hole drag in the Planckian plasma that develops in monolayer graphene in the vicinity of its Dirac point above liquid-nitrogen temperatures. The frequent electron-hole scattering forces minority carriers to move against the applied electric field due to the drag induced by majority carriers. This unidirectional transport of electrons and holes results in nominally negative mobility for the minority carriers. The electron-hole drag is found to be strongest near-room temperature, despite being notably affected by phonon scattering. Our findings provide better understanding of the transport properties of charge-neutral graphene, reveal limits on its hydrodynamic description and also offer insight into quantum-critical systems in general.
Cite
@article{arxiv.2410.10640,
title = {Extreme electron-hole drag and negative mobility in the Dirac plasma of graphene},
author = {L. A. Ponomarenko and Alessandro Principi and A. D. Niblett and Wendong Wang and R. V. Gorbachev and Piranavan Kumaravadive and A. I. Berdyugin and A. V. Ermakov and Sergey Slizovskiy and Kenji Watanabe and Takashi Taniguchi and Qi Ge and V. I. Fal'ko and Laurence Eaves and M. T. Greenaway and A. K. Geim},
journal= {arXiv preprint arXiv:2410.10640},
year = {2024}
}