光子晶体对太赫兹波的调制特性研究

利用传输矩阵方法研究了掺杂半导体n-GaAs/聚碳酸脂一维光子晶体的太赫兹波透射谱.研究结果发现,与一般由两种介电材料组成的一维光子晶体不同,由于掺杂半导体中自由载流子对太赫兹波存在较强的吸收,所以这种材料组成的一维光子晶体除可形成光子带隙外,还可以增强n-GaAs对太赫兹波的透射.同时还提出了一种基于这种一维光子晶体的太赫兹波调制器,通过外加电压控制半导体中电子浓度的大小可实现对太赫兹透射波幅度的调制. 关键词： 掺杂半导体光子晶体 太赫兹波 太赫兹波的调制

Research on modulation property of photonic crystals in terahertz range

In this work, the terahertz transimission spectrum through a one-demensional (1D) photonic crystal made from doped semiconductor n-GaAs/polycarbonate is studied by the transfer-matrix method. We show that, compared with most photonic crystals made from two different dielectrics, the doped semiconductor/dielectrics 1D photonic crystals can not only form the photonic gap, but also enhance the terahertz transmission through n-GaAs. We also propose and research a terahertz modulator based on the 1D photonic crystals, the transimitted terahertz waves through which can be modulated by different carrier densities in the semicondutor by varying the applied voltage.