双纳米棒周期结构的吸收特性和折射率敏感特性研究

Research on Absorption and Refractive Index Sensitivity of Periodic Structure of Double Nanorods

超材料完美吸收器在折射率传感器的研究中是非常重要的。利用时域有限差分方法,对表面等离激元结构进行仿真模拟。设计双纳米棒周期结构,根据阻抗匹配原理,优化顶层结构的参数,得到在波长12 mm左右时,结构对光波的吸收率达到99.6%。研究结构吸收光谱特性随结构周围空间介质折射率的变化,得到双纳米棒结构的灵敏度为4 008 nm/RIU,该结构可用来测量气体的折射率。

Super material perfect absorber is very important in the research of refractive index sensor. The finite difference time domain method is used to simulate the surface plasmon structure. According to the impedance matching principle,the parameters of the top layer structure are optimized. The absorption rate of the structure to the light wave is 99.6%,when the wavelength is about 12 micron. The sensitivity of the structure is 4 008 nm/RIU,and the structure can be used to measure the refractive index of gas.