Out-of-equilibrium criticalities in graphene superlattices

@article{Berdyugin2022OutofequilibriumCI,
  title={Out-of-equilibrium criticalities in graphene superlattices},
  author={Alexey I. Berdyugin and Na Xin and Haoyang Gao and Sergey Slizovskiy and Zhiyu Dong and Shubhadeep Bhattacharjee and Piranavan Kumaravadivel and Shuigang Xu and Leonid A. Ponomarenko and Matthew Holwill and D. A. Bandurin and Minsoo Kim and Yang Cao and Mark T. Greenaway and Kostya S. Novoselov and Irina V. Grigorieva and K. Watanabe and T. Taniguchi and Vladimir I. Fal’ko and Leonid S. Levitov and R. Krishna Kumar and SUPARNA DUTTASINHA},
  journal={Science},
  year={2022},
  volume={375},
  pages={430 - 433}
}
In thermodynamic equilibrium, current in metallic systems is carried by electronic states near the Fermi energy, whereas the filled bands underneath contribute little to conduction. Here, we describe a very different regime in which carrier distribution in graphene and its superlattices is shifted so far from equilibrium that the filled bands start playing an essential role, leading to a critical-current behavior. The criticalities develop upon the velocity of electron flow reaching the Fermi… 
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