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arXiv · 1512.02144

Scattering theory of the chiral magnetic effect in a Weyl semimetal: Interplay of bulk Weyl cones and surface Fermi arcs

P. Baireuther·J. A. Hutasoit·J. Tworzydło·C. W. J. Beenakker
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Abstract

We formulate a linear response theory of the chiral magnetic effect in a finite Weyl semimetal, expressing the electrical current density $j$ induced by a slowly oscillating magnetic field $B$ or chiral chemical potential $μ$ in terms of the scattering matrix of Weyl fermions at the Fermi level. Surface conduction can be neglected in the infinite-system limit for $δj/δμ$, but not for $δj/δB$: The chirally circulating surface Fermi arcs give a comparable contribution to the bulk Weyl cones no matter how large the system is, because their smaller number is compensated by an increased flux sensitivity. The Fermi arc contribution to $μ^{-1}δj/δB$ has the universal value $(e/h)^2$, protected by chirality against impurity scattering --- unlike the bulk contribution of opposite sign.

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P. Baireuther, J. A. Hutasoit, J. Tworzydło, C. W. J. Beenakker. 2016-03-30. Scattering theory of the chiral magnetic effect in a Weyl semimetal: Interplay of bulk Weyl cones and surface Fermi arcs. https://doi.org/10.1088/1367-2630%2F18%2F4%2F045009

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