Influence of surface termination on inverse Goos-H\"anchen shift of negatively refractive photonic crystals

TL;DR

This study investigates how surface termination affects the inverse Goos-Hänchen shift in 2D negatively refractive photonic crystals, revealing that surface modes significantly influence the shift magnitude.

Contribution

It demonstrates the strong dependence of inverse GH shift on surface termination and links it to the excitation of backward surface modes in 2D-NRPhCs.

Findings

Inverse GH shift varies with surface termination.

Large inverse GH shift occurs when surface modes are excited.

Coupling into surface modes depends on surface termination.

Abstract

The effect of surface termination on the inverse Goos Hanchen (GH) shift of two dimensional (2D) negatively refractive photonic crystal (NRPhC) containing air holes arranged in hexagonal lattice in a dielectric background is investigated for TM polarization. Results show that the magnitude of the inverse GH shift of 2DNRPhC strongly depends on surface termination even for an incident beam with a fixed frequency and incidence angle. Further study by calculating the dispersion of surface mode of 2D-NRPhC as a function of surface termination reveals that 2DNRPhC presents large inverse Goos Hanchen shift at those terminations where surface mode is excited, that is, large inverse Goos-Hanchen shift originates from backward surface mode of 2DNRPhC. In addition, the coupling coefficient of incident field into the field of surface mode as a function of surface termination is studied and demonstrates above results. This paper provides technical information regarding the combination of various functional photonic elements in the design of integrated optical circuits.