Hydrodynamic collective modes in graphene

Collective behavior is one of the most intriguing aspects of the hydrodynamic approach to electronic transport. Here we provide a consistent, unified calculation of the dispersion relations of the hydrodynamic collective modes in graphene. Taking into account viscous effects, we show that the hydrodynamic sound mode in graphene becomes overdamped at sufficiently large momentum scales. Extending the linearized theory beyond the hydrodynamic regime, we connect the diffusive hydrodynamic charge density fluctuations with plasmons.

Automated summary

The article presents a consistent and unified calculation of the dispersion relations of hydrodynamic collective modes in graphene, demonstrating that the sound mode becomes overdamped at large momentum scales. It also connects diffusive hydrodynamic charge density fluctuations with plasmons beyond the hydrodynamic regime.