Au纳米粒子周期阵列LSPR传感特性仿真研究

Analysis of LSPR sensing properties of Au nanoparticle periodic arrays

采用时域有限差分方法(FDTD),分别对Au纳米粒子在不同间距及不同尺寸下的消光光谱、吸收光谱和散射光谱进行仿真分析,在此基础上研究了Au纳米粒子的尺寸、间距变化对局域表面等离子体共振现象的影响.研究结果表明,随着纳米金球间距的减小,消光因子、吸收因子和散射因子峰值强度明显增大,且当L=R时峰值变化最剧烈;随着纳米金球半径的增大,其消光和吸收峰值波长出现蓝移现象,而散射因子发生了红移现象,但峰值强度均明显增大.

The extinction spectra, absorption spectra and scattering spectra of the Au nanoparticle arrays in different size and different spacing were simulated by the finite difference time domain. Based on this, the influence of the size and spacing of Au nanoparticles on LSPR phenomenon was studied. The simulation result demonstrates that the extinction, absorption and scattering wavelength peaks increase with the decreasing spacing. And the peak was the most dramatic when the spacing was equal to radius. With the increase of Au nanoparticle radius, the extinction and absorption wavelength peaks appear blue shift phenomenon, while scattering factors occurred red shift phenomenon, but all the peak intensity were significantly increased.