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arXiv · 1007.0175

Shielding of a moving test charge in a quantum plasma

D. Else·R. Kompaneets·S. V. Vladimirov
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Abstract

The linearized potential of a moving test charge in a one-component fully degenerate fermion plasma is studied using the Lindhard dielectric function. The motion is found to greatly enhance the Friedel oscillations behind the charge, especially for velocities larger than a half of the Fermi velocity, in which case the asymptotic behavior of their amplitude changes from 1/r^3 to 1/r^2.5. In the absence of the quantum recoil (tunneling) the potential reduces to a form similar to that in a classical Maxwellian plasma, with a difference being that the plasma oscillations behind the charge at velocities larger than the Fermi velocity are not Landau-damped.

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D. Else, R. Kompaneets, S. V. Vladimirov. 2010-08-31. Shielding of a moving test charge in a quantum plasma. https://doi.org/10.1103/physreve.82.026410

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