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arXiv · 1205.6354

Fermion condensation around a Coulomb impurity in a Weyl semimetal as a manifestation of the Landau zero-charge problem

Eugene B. Kolomeisky·Joseph P. Straley
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Abstract

A Coulomb impurity placed in an undoped Weyl semimetal spontaneously surrounds itself with a cloud of condensed Weyl fermions. We study this system within the Thomas-Fermi approximation. We find that the ground-state of the system is electrically neutral and exhibits an experimentally accessible Landau zero-charge effect: the impurity charge is screened out at any finite distance in the limit of vanishing impurity size. Specifically, we show how in this limit the Thomas-Fermi equation for the electrostatic potential transforms into the Gell-Mann-Low equation for the charge.

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Eugene B. Kolomeisky, Joseph P. Straley. 2012-05-31. Fermion condensation around a Coulomb impurity in a Weyl semimetal as a manifestation of the Landau zero-charge problem. https://arxiv.org/abs/1205.6354

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