Left/right asymmetry in reflection and transmission by a planar anisotropic dielectric slab with topologically insulating surface states

Akhlesh Lakhtakia,Tom G Mackay

doi:10.1117/1.jnp.10.020501

Akhlesh Lakhtakia, Tom G Mackay

Open Access

https://doi.org/10.1117/1.jnp.10.020501

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Abstract

The reflection and transmission of plane waves by a homogeneous anisotropic dielectric slab—as represented by a columnar thin film—with topologically insulating surface states was theoretically investigated. Copolarized and cross-polarized reflectances and transmittances were calculated by solving the associated boundary-value problem. Numerical calculations revealed that all four reflectances and all four transmittances were asymmetric with respect to reversal of projection of the propagation direction of the incident plane wave on the illuminated surface of the slab. This left/right reflection and transmission asymmetry arises due to the combined effects of the slab’s anisotropy and surface states.

Highlights

The modest aim of this communication is to theoretically show that a homogeneous anisotropic dielectric slab with topologically insulating surface states (TISS)[1,2] reflects and transmits light in such a way as to exhibit asymmetry with respect to reversal of projection of the propagation direction of the incident plane wave on the illuminated surface of the slab
A homogeneous anisotropic material is characterized by a frequency-dependent relative permittivity dyadic ε
Optical scattering by isotropic dielectric materials, i.e., ε 1⁄4 εðu^ xu^ x þ u^ yu^ y þ u^ zu^ zÞ, with TISS has been investigated theoretically[4,5,6,7] as well as experimentally,[2,8] this communication is possibly the first report of optical scattering by an anisotropic dielectric material with TISS. The existence of such materials is deemed possible because the isotropic materials with TISS are chalcogenides,[1,2] columnar thin films (CTFs) of other chalcogenides have been fabricated,[9] and CTFs function as anisotropic dielectric materials at sufficiently low frequencies.[10]

Summary

Introduction

The modest aim of this communication is to theoretically show that a homogeneous anisotropic dielectric slab with topologically insulating surface states (TISS)[1,2] reflects and transmits light in such a way as to exhibit asymmetry with respect to reversal of projection of the propagation direction of the incident plane wave on the illuminated surface of the slab. Lakhtakia and Mackay: Left/right asymmetry in reflection and transmission by a planar anisotropic dielectric. We have found that the TISS induce the exhibition of left/right asymmetry in reflection and transmission by a homogeneous anisotropic dielectric slab.

Results

Conclusion