The role of the defect in photonic crystals based on WS2 or WSe2 monolayers: a vision on how to achieve high quality factor and wavelength adjustability in defect modes

• Published in: Optical and quantum electronics Vol. 55; no. 4
• Main Authors: Ansari, Narges, Mohebbi, Ensyieh, Nazari, Effat
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.04.2023; Springer Nature B.V
• Subjects: Absorption; Asymmetric structures; Asymmetry; Characterization and Evaluation of Materials; Computer Communication Networks; Crystal defects; Electrical Engineering; Lasers; Monolayers; Optical Devices; Optics; Photoelectricity; Photonic band gaps; Photonic crystals; Photonics; Photovoltaic cells; Physics; Physics and Astronomy; Q factors; Silicon dioxide; Solar cells; Symmetry; Thickness; Transition metal compounds; Tungsten disulfide; Defective photonic crystals; Absorption; Symmetric and asymmetric structures; Full width half maximum; Two-dimensional transition metal dichalcogenides
• ISSN: 0306-8919; 1572-817X
• DOI: 10.1007/s11082-022-04282-7

Two-dimensional transition metal dichalcogenides materials play a pivotal role in photonics. Their placement in photonic crystals was proved effective in enhancing the absorption for a wide range of applications. In this paper, we study the symmetric and asymmetric defective photonic crystals (DPC) whose defects are formed by DMD where M indicates the WS 2 or WSe 2 monolayer and D represents SiO 2 layer. The present study investigates the effects of the position of the defect layer in DPC on the absorption, FWHM, quality factor, number, and wavelength of the defect modes in both symmetric and asymmetric structures. We show that the amount of the absorption of defect modes in the case of WSe 2 and WS 2 is above 93% and 80% in symmetric and asymmetric structures, respectively. Further, in symmetric structures, FWHM of WS 2 is broader than that of WSe 2 ; in asymmetric structures, on the other hand, FWHM of WSe 2 is wider than that of WS 2 . Also, Photonic band gap does not depend on the thickness of the defect layer, the symmetry or asymmetry of the structure, periodicity of the top and bottom defect layer of DMD. The proposed structures are likely to attract the attentions to their applications in photoelectric detectors, absorbent filters, solar cells, and the like.