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arXiv · 1712.05946

Kelvin-Mach wake in a two-dimensional Fermi sea

Eugene B. Kolomeisky·Joseph P. Straley
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Abstract

The dispersion law for plasma oscillations in a two-dimensional electron gas in the hydrodynamic approximation interpolates between $\Omega \propto \sqrt{q}$ and $\Omega \propto q$ dependences as the wave vector $q$ increases. As a result, downstream of a charged impurity in the presence of a uniform supersonic electric current flow, a wake pattern of induced charge density and potential is formed whose geometry is controlled by the Mach number $M$. For $1 \sqrt{2}$. These wakes also trail an external charge traveling supersonically a fixed distance away from the electron gas.

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Eugene B. Kolomeisky, Joseph P. Straley. 2017-12-16. Kelvin-Mach wake in a two-dimensional Fermi sea. https://doi.org/10.1103/physrevlett.120.226801

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