Scattering theory of the chiral magnetic effect in a Weyl semimetal: interplay of bulk Weyl cones and surface Fermi arcs
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 infinitesystem limit for δ j/δ μ , but not for δ j/δ B: 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}δ j/δ B has the universal value {(e/h)}^{2}, protected by chirality against impurity scattering—unlike the bulk contribution of opposite sign.
 Publication:

New Journal of Physics
 Pub Date:
 April 2016
 DOI:
 10.1088/13672630/18/4/045009
 arXiv:
 arXiv:1512.02144
 Bibcode:
 2016NJPh...18d5009B
 Keywords:

 Condensed Matter  Mesoscale and Nanoscale Physics
 EPrint:
 8 pages, 8 figures