Graphene - a nearly perfect fluid

Markus Mueller; Joerg Schmalian; Lars Fritz

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arXiv · 0903.4178

Graphene - a nearly perfect fluid

Markus Mueller·Joerg Schmalian·Lars Fritz

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Abstract

Hydrodynamics and collision dominated transport are crucial to understand the slow dynamics of many correlated quantum liquids. The ratio η/s of the shear viscosity ηto the entropy density s is uniquely suited to determine how strongly the excitations in a quantum fluid interact. We determine η/s in clean undoped graphene using a quantum kinetic theory. As a result of the quantum criticality of this system the ratio is smaller than in many other correlated quantum liquids and, interestingly, comes close to a lower bound conjectured in the context of the quark gluon plasma. We discuss possible consequences of the low viscosity, including pre-turbulent current flow.

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Markus Mueller, Joerg Schmalian, Lars Fritz. 2009-07-14. Graphene - a nearly perfect fluid. https://arxiv.org/abs/0903.4178

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