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arXiv · 1801.01495

Electronic sound modes and plasmons in hydrodynamic two-dimensional metals

Andrew Lucas·Sankar Das Sarma
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Abstract

Using an analytically tractable kinetic model of a two dimensional Fermi liquid of electrons, we characterize the crossovers between zero sound, first sound and plasmons. For experimentally realized Fermi liquids in a hydrodynamic limit, both zero and first sound waves are essentially replaced by plasmons. The plasmon dispersion relation is robust against hydrodynamic effects, up to acquiring the viscous-limited decay rate of a first sound wave in the hydrodynamic limit. We discuss implications for experiments in clean two dimensional electron gases.

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Andrew Lucas, Sankar Das Sarma. 2018-03-28. Electronic sound modes and plasmons in hydrodynamic two-dimensional metals. https://doi.org/10.1103/physrevb.97.115449

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