石墨烯纳米带修饰微悬臂梁的光热偏转特性研究

摘要

To solve the low absorbance of the traditional bimaterial cantilever,a method exploring the surface plasmons in gra-phene nanoribbon was proposed to improve the photothermal deflection sensitivity of the microcantilever.Firstly,an optical mod-el of the cantilever was built based on the finite element method.The absorbance of the cantilever can be improved up to 100% by optimizing the structure parameters of the graphene nanoribbon and the cantilever.Secondly,the thermodynamic model of the cantilever was also built using Ansys software,and the influence of the laser parameters on the photothermal deflection character-istics of cantilever was also investigated.Simulation results showed that the sensitivity of the graphene nanoribbon decorated can-tilever was 5 times larger than that of the traditional bimaterial cantilever at 10.7 μm,and 4 times within a wide range of infrared waveband from 9.5-13.5 μm.%针对传统双层悬臂梁存在吸收效率低的难题，提出了一种通过激发石墨烯纳米带表面等离激元以提高悬臂梁光热偏转特性的方法。首先，基于有限元法建立了石墨烯纳米带修饰微悬臂梁的光学模型，并通过优化石墨烯纳米带及悬臂梁的结构参数，实现了对入射光波的完美吸收（100％）；其次，建立了悬臂梁的热力学模型，采用 Ansys 软件仿真计算了脉冲激光参数对悬臂梁光热偏转特性的影响。结果表明：在波长为10．7μm 处，石墨烯纳米带修饰微悬臂梁的光热偏转灵敏度是传统双层悬臂梁光热偏转灵敏度的5倍，并且，在9．5～13．5μm 的整个宽波段范围内，石墨烯纳米带修饰微悬臂梁的光热偏转灵敏度均大于传统双层悬臂梁光热偏转灵敏度的4倍。