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.

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石墨烯中的流体动力集体模式

集体行为是电子传输流体动力学方法中最吸引人的方面之一。在这里，我们提供了对石墨烯中流体动力集体模态的色散关系的一致，统一的计算。考虑到粘性效应，我们表明，在足够大的动量尺度下，石墨烯中的流体动力声模变得过度阻尼。将线性化理论扩展到流体力学范围之外，我们将扩散流体动力学电荷密度波动与等离激元联系起来。