Designing Plane Wave Modulators Using 1dpc Nanostructure With R-Grin Defect Layer

Abstract

Abstract-In this paper, we introduce plane wave modulators that are designed using one-dimensional photonic crystals (1DPC) containing radial gradient refractive index (r-GRIN) defect layers. Three kinds of r-GRIN materials with different refractive index distribution functions are applied in numerical analysis. The properties of the phase and intensity of the transmitted plane wave beam through proposed structures are studied using the transfer matrix method. Radially-dependent defect modes, modulated phase and intensity are obtained according to the refractive index distribution functions. The results are predictable by regarding the Bragg condition and destructive interference, which are the origins of the photonic band gap (PBG). Due to the radial-dependency of the defect layer's refractive index, the rays passing through different transverse positions experience different optical pathways. Therefore, the defect modes and transmitted spectrum (phase and amplitude) vary transversely. This study demonstrates another ability of the artificial PC structures to design plane wave modulators and manipulate its phase and intensity.

Petal-shaped optical vortice generation by a graded-index defective 1DPC nanostructure under irradiation of a Gaussian beam

“…In our previous works [13][14][15], in terms of enhancing PBG properties, we introduced some laser beam shapes designed by one-dimensional photonic crystal (1DPC) structures. The proposed structures have the capability of modulating the defect mode and output phase and intensity of the incident plane wave by changing the incident beam's frequency and the defect layer's refractive index distribution function.…”