paper

Topological Magneto-Electric Effect Decay

arXiv:1207.4444 · doi:10.1103/PhysRevLett.111.016801

Abstract

We address the influence of realistic disorder on the effective magnetic monopole that is induced near the surface of an ideal topological insulator (TI) by azimuthal currents which flow in response to a suddenly introduced external electric charge. We show that when the longitudinal conductivity is accounted for, the apparent position of a magnetic monopole initially retreats from the TI surface at speed , where is the fine structure constant and is the speed of light. For the particular case of TI surface states described by a massive Dirac model, we further find that the temperature T=0 Hall currents vanish once the surface charge has been redistributed to screen the external potential.

4.5 pages, 1 figure

References in corpus (13)

Cited by in corpus (11)