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In recent years, two-dimensional materials such as MoS2 monolayers have attracted a lot of attention due to their high absorption. This study proposes the use of MoS2 monolayers as part of the defect in Fibonacci and Thue-Morse defective quasiphotonic crystals (DQPCs) to create an adjustable defect mode with relatively high absorption. The wavelength adjustability of the defect mode is investigated by parameters such as generation number, periodicity, and type of sequence used in DQPCs. The results revealed that using DQPCs can help enhance absorption and enables the adjustment of the defect mode as its generation number changes. Moreover, a Fibonacci DQPC generally requires much fewer layers in comparison to a Thue-Morse DQPC. To conclude, it is possible to achieve a wavelength-adjustable absorption of more than 90% with a Fibonacci DQPC.

2D molybdenum disulfide MoS2, has represented potential applications in optoelectronic devices based on their promising optical absorption responses. However, for practical applications, absorption should increase furthermore in a wide wavelength window. In this paper, we design Fibonacci photonic crystals (PCs) based on Si, SiO2 and MoS2 monolayer and we calculate their absorption responses based on the transfer matrix method. The optical refractive index of the MoS2 monolayer was determined based on the Lorentz–Drude–Gauss model. Effects of Fibonacci order, periodicity, incident light angle and polarization are included in our calculations. Finally, an absorption as large as 90% in a wide optical wavelength range is achieved for both polarizations and incident angle down to 60°. Our results are useful for designing photonic devices with high absorption efficiency.

A defective Thue–Morse quasi-photonic crystal containing molybdenum disulfide (MoS2) is suggested to construct an ultra-narrowband multiple resonant absorber in the visible range. Multiple high absorption peaks can be achieved by altering the design of the proposed structure in different ways such as changing the generation number or the symmetry with respect to defect. Two structures are introduced, which create more than seven absorption peaks higher than 40% and one of the peaks about 100%. Defect modes' wavelength can be tuned to show the blue shift by incident angles and the polarization of light. Our optimal structures are useful for applications in multiplex filters and multiple channel sensors due to their high amount and narrowband absorption peaks and can show nearly perfect absorption.

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