Polarization - dependent tunneling of light in gradient optics

TL;DR

This paper investigates how gradient dielectric nanofilms affect the tunneling and reflection of polarized light, revealing conditions for complete transmission and strong reflection useful for optical device applications.

Contribution

It provides exact analytical models for polarization-dependent tunneling and reflection in gradient photonic barriers, highlighting non-local dispersion effects and optical anisotropy.

Findings

Narrow-band non-attenuated S-wave tunneling through barriers.

Spectral regions with strong P-wave reflection.

Potential applications in miniaturized polarizers and filters.

Abstract

Reflection-refraction properties of photonic barriers, formed by dielectric gradient nanofilms, for inclined incidence of both S- and P-polarized electromagnetic (EM) waves are examined by means of exactly solvable models. We present generalized Fresnel formulae, describing the influence of the non-local dispersion on reflectance and transmittance of single- and double-layer gradient photonic barriers for S- and P- waves and arbitrary angles of incidence. The non-local dispersion of such layers, arising due to a concave spatial profile of dielectric susceptibility across the plane film, is shown to result in a peculiar heterogeneity - induced optical anisotropy, providing the propagation of S(P) waves in tunneling (travelling) regimes. The results obtained indicate the possibility of narrow-band non-attenuated tunneling (complete transmittance) of oblique S- waves through such heterogeneous barriers, and the existence of spectral areas characterized by strong reflection of P-waves and deep contrast between transmitted S- and P-waves. The scalability of obtained exact analytical solutions of Maxwell equations into the different spectral ranges is discussed and the application potential of these phenomena for miniaturized polarizers and filters is demonstrated.