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arXiv · 1806.03231

Fluidity Onset in Graphene

Denis A. Bandurin·Andrey V. Shytov·Leonid Levitov·Roshan Krishna Kumar·Alexey I. Berdyugin·Moshe Ben Shalom·Irina V. Grigorieva·Andre K. Geim·Gregory Falkovich
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Abstract

Viscous electron fluids have emerged recently as a new paradigm of strongly-correlated electron transport in solids. Here we report on a direct observation of the transition to this long-sought-for state of matter in a high-mobility electron system in graphene. Unexpectedly, the electron flow is found to be interaction-dominated but non-hydrodynamic (quasiballistic) in a wide temperature range, showing signatures of viscous flows only at relatively high temperatures. The transition between the two regimes is characterized by a sharp maximum of negative resistance, probed in proximity to the current injector. The resistance decreases as the system goes deeper into the hydrodynamic regime. In a perfect darkness-before-daybreak manner, the interaction-dominated negative response is strongest at the transition to the quasiballistic regime. Our work provides the first demonstration of how the viscous fluid behavior emerges in an interacting electron system.

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Denis A. Bandurin, Andrey V. Shytov, Leonid Levitov, Roshan Krishna Kumar, Alexey I. Berdyugin, Moshe Ben Shalom, Irina V. Grigorieva, Andre K. Geim, Gregory Falkovich. 2018-06-08. Fluidity Onset in Graphene. https://doi.org/10.1038/s41467-018-07004-4

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