基于石墨烯的布洛赫表面波调控特性研究

布洛赫表面波(Bloch surface wave,BSW) 具有传输损耗低、显著表面局域场增强、环境敏感等特性,因而被视为研究近场光和物质相互作用的关键技术。其主要在截断的一维光子晶体与外界介质的界面激发并沿此界面传播,通过传播界面微纳结构的设计,可在纳米尺度实现对BSW的有效调控。本文从BSW的模式特性出发,提出了石墨烯加载的一维光子晶体BSW传感器件结构。通过改变石墨烯层的结构参数,调节激发模式在光子带隙中的位置,研究激发模式的光场传输特性,实现对BSW激发波长、振幅和相位的调控。进一步利用其对外界介质折射率变化非常敏感的特性,对其传感检测能力进行研究。结果表明,该器件有望实现高灵敏度的生化传感检测应用。该研究为新型BSW集成光子器件的设计与发展提供了新思路。

The manipulation of Bloch surface wave based on graphene

The Bloch surface wave (BSW) has the properties of low transmission loss,significant local field enhancement at the surface as well as sensitive to the environment,which has been regarded as one of the key solutions for the study of near field light-matter interaction.BSW mainly propagates along the truncated one-dimensional photonic crystal and the external medium,the manipulation of BSW can be realized at the nanometer scale via the micro-nano structural design of the propagation interface.Here,embarking from the optical properties of BSW mode,a graphene loaded one-dimensional photonic crystal BSW sensor structure is proposed.The existence of the excited mode in the band-gap can be determined by tuning the structural parameters of the graphene layer.Through investigating the optical field transmission characteristics of the excited mode,the manipulation of the excited wavelength,intensity as well as phase of the sustained BSW mode can be achieved.Moreover,leveraging its sensitivity to the refractive index change of the external medium,the sensing detection capability of this proposed structure is discussed.The results demonstrate that the proposed sensor structure is expected to achieve highly sensitive biochemical sensing detection applications.The study provides a new route for the design and development of new BSW integrated photonic devices.