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arXiv · 2006.02022

Magnetic-conductivity effects on electromagnetic propagation in dispersive matter

Pedro D. S. Silva·Manoel M. Ferreira Jr.·Marco Schreck·Luis F. Urrutia
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Abstract

The Chiral Magnetic Effect (CME) has been investigated as a new transport phenomenon in condensed matter. Such an effect appears in systems with chiral fermions and involves an electric current generated by a magnetic field by means of an "exotic" magnetic conductivity. This effect can also be connected with extensions of the usual Ohm's law either in magnetohydrodynamics or in Lorentz-violating scenarios. In this work, we study the classical propagation of electromagnetic waves in isotropic dispersive matter subject to a generalized Ohm's law. The latter involves currents linear in the magnetic field and implies scenarios inducing parity violation. We pay special attention to the case of a vanishing electric conductivity. For a diagonal magnetic conductivity, which includes the CME, the refractive index is modified such that it implies birefringence. For a nondiagonal magnetic conductivity, modified refractive indices exhibiting imaginary parts occur ascribing a conducting behavior to a usual dielectric medium. Our findings provide new insight into typical material properties associated with a magnetic conductivity.

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Pedro D. S. Silva, Manoel M. Ferreira Jr., Marco Schreck, Luis F. Urrutia. 2020-06-03. Magnetic-conductivity effects on electromagnetic propagation in dispersive matter. https://doi.org/10.1103/physrevd.102.076001

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