THz波段亚波长半导体球形阵列光学特性的数值模拟

Numerical simulation on optical properties of subwavelength semiconductor sphere arrays in THz frequency range

利用T-matrix方法对太赫兹波段亚波长半导体球形阵列进行了数值模拟并在数值模拟结果的基础上讨论了其光学特性。在太赫兹波段可以通过掺杂等手段调节半导体的表面等离子体特性。以半导体InSb为例并采用Drude模型,对单个亚波长球及两个或多个亚波长球组成的阵列进行了数值模拟,主要以归一化消光截面为参数,讨论了不同阵元半径、不同球形单元间距、不同单元数目及入射波不同极化方向对阵列特性的影响。

The subwavelength semiconductor sphere arrays in THz range are simulated with T-matrix method. Based on the numerical results, their optical properties are also discussed. The properties of semiconductor surface plasmon can be tailored within the terahertz frequency range through doping. We take the semiconductor InSb as an example and adopt Drude model for simulating single subwavelength sphere and arrays with two or more subwavelength spheres. In addition, we discuss the effects of some parameters on the properties of sphere arrays, such as the sphere radius, periodicity of the array, the number of spheres in the array and the polarization direction of the incident wave. The result gives a preliminary comprehension on the optical properties of subwavelength semiconductor sphere arrays and provides some theoretical help for their potential applications.