Photonic band gaps extension in one dimensional metallo-organic multilayer photonic structure: Reflectance Spectra of Ag/N, N-bis-(1-naphthyl)-N, Ndiphenyl-1; 1biphenyl-4; 4diamine

Abstract

In this paper, we show theoretically that the reflectivity of one dimensional multilayer metalorganic periodic structure (1D MOPS) can be enhanced due to the addition of the organic constituents. We have used simple transfer matrix method to calculate the absorption, transmittance and reflectance of the 1D MOPS-systems. The organic component like N, N-bis-(1naphthyl)-N, Ndiphenyl-1; 1biphenyl-4; 4diamine (NPB) absorbs the light in ultra-violet, visible and infrared electromagnetic region and the structure with Ag-metal also tend to absorb the light by the plasmaonic action and their refractive index can be calculated from Drude equation. The reflectance spectra of multilayer 1D MOPS containing a variable number periodic of Ag/N, N-bis-(1-naphthyl)-N, Ndiphenyl-1; 1biphenyl-4; 4diamine (NPB) structure are calculated taking optical constant of NPB and Ag. The optical band gap and reflectance spectra of 1D MOPS of the considered structure is obtained in the visible and near infrared regions either with the variation of the metal layer thickness or thickness of the organic layer. From the results under investigation through TMM, tunability in the optical band gap was observed either change in thickness of the other layer 1/ or 2 or the angle of the incident. Due to optical absorption of the light in the different region of electromagnetic spectrum, either N, N-bis-(1-naphthyl)-N, Ndiphenyl-1; 1biphenyl-4; 4diamine (NPB) or silver metal, the optical band gap of 1DMOPS shows the shift of band edges of lL and lR from ultra-violet to visible and the infra-red with changing the optical constant.