本文设计了一种基于空气圆盘串的二维表面等离子体光栅光吸收器,采用二维时域有限差分法(2D-FDTD)对该吸收器的平均吸收率随其几何结构参数的依赖关系进行了分析。结果表明:在可见光波段,空气圆盘串上圆盘的层数对该吸收器的吸收效果有较大的影响,层数越多,吸收效果越好。在层数一定的情况下,圆盘的半径、相邻圆盘串之间的中心距离、同一圆盘串上相邻圆盘的圆心之间的距离,相互影响,相互牵连。通过对吸收特性的优化,给出了优化结构参数。这种表面等离子体光栅光吸收器可应用于薄膜太阳能电池、传感器、滤波器、成像、热辐射和探测等多个领域。

A kind of 2D surface plasmonic grating optical absorber based on air disk strings was designed in this paper.The effects of the geometrical parameters on its average absorption rate were analyzed by a two-dimensional Finite-Difference Time-Domain (2D-FDTD) method.Results showed that,the layer of air disks of the string has a great influence on the absorption effect in the visible spectrum and the absorption will be better with the more layers.The radius of the air disk,the center distance between adjacent air disk strings and the center distance between adjacent air disks of the string influence each other when the number of layers is fixed.The optimized structure parameters were set by optimizing the absorption characters.This absorber can be used for thin film solar cells,sensor,filter,imaging,thermal radiation,detection and other fields.