Performance Analysis of High Broadband Optical Absorption by MoSe2 Monolayer in Octonacci Quasi-Photonic Crystal

In comparison to the zero band gap of graphene, semiconductor transition metal dichalcogenides (TMDCs) have bandgaps in the close-infrared to the visible range. These materials are known to have direct band gaps in the monolayer limit, a feature well suited for applications and developments in photonics and optoelectronics. Many optoelectronic devices are designed with 2D TMDCs because of their high optical absorption characteristics. In this article, we propose using one-dimensional (1D) Octonacci quasi-photonic crystals composed of MoSe
₂
and dielectric materials such as SiO
₂
, Si
₃
N
₄
, and PMMA. On the basis of the transfer matrix process, the absorption responses of the proposed structures are studied. It can be observed that quasi-periodic photonic crystals consist of different mathematical patterns (such as Octonacci pattern) which can cause enhanced wide band absorption at tunable wavelengths through the variation of the layer thicknesses and the number of periodicities. The effects of incident angle are also taken into consideration. It is found that quasi-photonic crystals of Octonacci sequence based on MoSe
₂
monolayer are capable of acting as broadband and broad-angle absorbers in the visible spectrum. One important aspect of the findings regarding wide band and wide angle absorption is that for a large number of periods, above 90% absorption is achieved throughout the entire visible band and absorption close to 80% is obtained for large incident angles with values up to 70 degrees.