Hybrid graphene-molybdenum disulphide based ring resonator for label-free sensing

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• 作者：Farzad Zangeneh-Nejad ; ^{fr.zangeneh@gmail.com" class="auth_mail" title="E-mail the corresponding author} ; Reza Safian ^{rsafian@cc.iut.ac.ir" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Label-free sensing ; Graphene ; Molybdenum disulphide ; Ring resonator ; Surface plasmon
• 刊名：Optics Communications
• 出版年：2016
• 出版时间：15 July 2016
• 年：2016
• 卷：371
• 期：Complete
• 页码：9-14
• 全文大小：1111 K

文摘

In this paper, a novel graphene–MoS₂ hybrid structure based surface plasmon resonance sensor is presented for label-free analysis. The structure consists of a silicon nitride (Si₃N₄) dielectric layer vertically coupled to a thin layer of metallic strip made of silver (Ag) on top. A hybrid graphene–MoS₂ layer is added on top of the metallic strip to enhance the sensitivity and the quality factor of the sensor. The cladding layer is assumed to be porous alumina (p-Al₂O₃) increasing the interaction of the surface plasmon mode and the target molecules. Finite difference time domain analysis (FDTD) has been used to design and to analyze the performance of the sensor. It is shown that by addition of hybrid graphene–MoS₂ layer to the structure of a surface plasmon resonance based sensor, the refractive index sensitivity and the intrinsic quality factor of the sensor are enhanced simultaneously. It is also shown that addition of the hybrid graphene–MoS₂ layer leads to higher values of figure of merit (FOM) for the sensor, and consequently better performance of the sensor. Moreover, the effect of increasing the number of graphene and MoS₂ layers is investigated. The proposed sensor is very compact and can be used for lab-on-a-chip sensing applications.