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Study of super absorption properties of 1D graphene and dielectric photonic crystal for novel applications Asish Kumar1 · Pawan Singh1 · Khem B. Thapa1 Received: 20 December 2019 / Accepted: 12 September 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract In this article, we have theoretically analyzed the variation of real and imaginary components of electric permittivity and also the variation of refractive index of the graphene material in the Terahertz frequency range. The optical characteristics of One-Dimensional Periodic Structure (1-DPS) of graphene and dielectric materials have analyzed using Transfer Matrix Method. The transfer matrix method is very eminent method to analyze the optical characteristics of 1-DPS like dispersion relation, phase velocity, group velocity, reflection, transmission and absorption characteristics, etc. The absorption characteristics of considered graphene-based multilayered periodic structure have been analyzed with the variation of chemical potential ( 𝜇c ) of the graphene layer. The calculated absorption spectra of considered 1-DPS at the certain threshold frequency have found high and threshold value for the high chemical potential (gate voltage) of the graphene having the large thickness of the dielectric layer. Such the high and threshold absorption property of graphenebased 1-DPS, which acts as super absorber at terahertz region of the electromagnetic spectrum, may be used for the novel super absorber applications. Keywords  Graphene · Dielectric · Multilayer structure · Chemical potential · Superabsorption · TMM

1 Introduction Photonic Crystals (PCs) are periodic structures of dielectric materials with the periodic modulation of dielectric constant of two or more media varied in the space. Yablonovitch and John studied the origin of Photonic Band Gap (PBG) of the PCs in the year 1987 (Yablonovitch 1987; John 1987). PCs are the more attractive optical media due to their abnormal properties of the PBG in respective to control the electromagnetic radiations (photons). Photonic crystal has unique feature of the photonic band gap where a specific domain of frequencies cannot be allowed to propagate from periodically structured materials. Therefore, PBG has the great applications in science and technology in controlling the flow of * Khem B. Thapa [email protected] 1



Department of Physics, School of Physical and Decision Sciences, Babasaheb Bhimrao Ambedkar University, Lucknow, U.P. 226025, India

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electromagnetic radiation. The wave propagation inside the periodic structure, PC, depends on the properties of materials: refractive index, unit cell, filling fraction, frequency and dimensionality, etc. (Joannopolos et al. 2007). One-dimensional periodic structure, called One-Dimensional Photonic Crystal (1-DPC), is the simplest periodic structure where the direction of wave propagation in the structure is considered in one dimension of the space. Besides this, 1-DPC can be easily fab