有限厚度金属狭缝对太赫兹脉冲的整形和滤波

Spatiotemporal shaping and filtering of terahertz pulses through metal slits with finite thickness

用时域有限差分算法(FDTD)分析了有限厚度金属狭缝对太赫兹(THz)脉冲进行时空整形的效应和特性.分析表明:这种基于衍射方法的准光学技术手段对横向磁场(TM)模式THz脉冲有很好的整形和滤波作用,而对横向电场(TE)模式THz脉冲几乎没有整形和滤波作用,并运用平面光波导理论对所获得的数据模拟结果进行了定性说明.这些分析结果可在相关实验中予以考虑和采用.

The characteristics of spatiotemporal shaping and filtering of terahertz （THz） pulses passing through metal slits with finite thickness have been investigated by employing the finite-difference time-domain （FDTD） method. It is shown that this diffraction-based quasi-optical technique has a good influence on shaping and filtering of transverse magnetic（TM） polarized THz pulse, while has no effect on transverse electric（TE） polarized THz pulse. Furthermore, the numerical simulation results have been interpreted qualitatively by the planar waveguide theory and can be employed in the relevant experiments.