Theory of topological insulator waveguides: polarization control and the enhancement of the magneto-electric effect.

ABSTRACT: Topological insulators subject to a time-reversal-symmetry-breaking perturbation are predicted to display a magneto-electric effect that causes the electric and magnetic induction fields to mix at the material's surface. This effect induces polarization rotations of between ?1-10?mrad per interface in an incident plane-polarized electromagnetic wave normal to a multilayered structure. Here we show, theoretically and numerically, that by using a waveguide geometry with a topological insulator guide layer and magneto-dielectric cladding it is possible to achieve rotations of ?100?mrad and generate an elliptical polarization with only a three-layered structure. This geometry is beneficial, not only as a way to enhance the magneto-electric effect, rendering it easier to observe, but also as a method for controlling the polarization of electromagnetic radiation.

SUBMITTER: Crosse JA 

PROVIDER: S-EPMC5318882 | biostudies-other | 2017 Feb

REPOSITORIES: biostudies-other