Symmetrical Fibonacci polymeric photonic multilayers: light localization and elasto-optic effect

In this study, we examine the modulation of light transmission via a one-dimensional polymeric symmetrical Fibonacci-multilayer. The multilayer is constructed using substitutional generalised Fibonacci using PMMA and PS as the constituent materials. The widely recognised transfer matrix approach is utilised to derive theoretical results. The results of our investigation indicate that the width, spacing, and depth of the PBG can be modified by choosing the proper generation number. Remarkably, the count of significant PBGs remains consistent throughout all generation numbers, with the exception of the \(10^{th}\) ${10}^{\mathit{th}}$ generation symmetrical Fibonacci-multilayer, which exhibits a pronounced localization. As the generation number grows, a symmetrical shift of the PBGs is noticed in relation to their position. Moreover, it has been shown that the forbidden frequency range can be adjusted by changing the hydrostatic pressure applied. The rise in pressure causes a shift in the frequency spectrum towards higher frequencies. Furthermore, our findings indicate that augmenting the polymer thickness leads to a shift towards longer wavelengths, known as a redshift, in the PBGs. This paper presents a new method for creating optical devices, specifically multi-band tunable optical filters and durable optical sensors, using one-dimensional polymeric symmetrical Fibonacci multilayers.