Yang Jianfeng, Yang Jingjing, Deng Wei, Mao Fuchun, Huang Ming
Opt Express. 2015 Dec 14;23(25):32289-99. doi: 10.1364/OE.23.032289.
In this paper, a cylindrical graphene plasmon waveguide (CGPW), which consists of two rolled graphene ribbons, a dielectric core and a dielectric interlayer is proposed, and its use for molecular sensing is investigated. First, an analytical model for the surface plasmon modes supported by this graphene geometry is presented and verified by finite element method simulations. Furthermore, we demonstrate a large tunability of the modes behavior by varying the Fermi level of the graphene, the coupling distance between the two sheets and the radius of the cylinder. Finally, a molecular sensing scheme based on the CGPW is proposed. Broadband spectroscopy of ethanol and toluene thin layers is realized by recording the changes in spectral intensity of the propagating mode. Due to the broadband localization capability of graphene plasmon mode which leads to a strong light-matter interaction in the midinfrared and terahertz regime, the proposed sensing scheme may provide an effective way for detecting nanometric-size molecules.
本文提出了一种由两条卷曲石墨烯带、一个介质芯和一个介质夹层组成的圆柱形石墨烯等离子体波导（CGPW），并研究了其在分子传感中的应用。首先，给出了由这种石墨烯结构支持的表面等离子体模式的解析模型，并通过有限元方法模拟进行了验证。此外，我们通过改变石墨烯的费米能级、两片之间的耦合距离和圆柱体半径，证明了模式行为的大可调谐性。最后，提出了一种基于CGPW的分子传感方案。通过记录传播模式的光谱强度变化，实现了乙醇和甲苯薄层的宽带光谱。由于石墨烯等离子体模式的宽带局域化能力，导致在中红外和太赫兹波段有强光与物质的相互作用，所提出的传感方案可能为检测纳米尺寸的分子提供一种有效的方法。
