Weyl fermions induced Magnon electrodynamics in Weyl semimetal

Jimmy A. Hutasoit, Jiadong Zang, Radu Roiban, Chao-Xing Liu

Published 2014-05-02, updated 2014-10-16Version 2

Weyl fermions, which are fermions with definite chiralities, can give rise to anomalous breaking of the symmetry of the physical system which they are a part of. In their (3+1)-dimensional realizations in condensed matter systems, i.e., the so-called Weyl semimetals, this anomaly gives rise to topological electromagnetic response of magnetic fluctuations, which takes the form of non-local interaction between magnetic fluctuations and electromagnetic fields. We study the physical consequences of this non-local interaction, including electric field assisted magnetization dynamics, an extra gapless magnon dispersion, and polariton behaviors that feature "sibling" bands in small magnetic fields.