空位缺陷对PBG型THz光子晶体光纤特性的影响

Point defects' affect on the PBG-type THz photonic crystal fiber characteristics

研究空位缺陷对PBG型THz光子晶体光纤(PBG-TPCF)的带隙和泄漏损耗两种特性的影响。计算表明空位缺陷都使PBG-TPCF的带隙宽度减少并使中心频率不同程度地上移;最低损耗点由于带隙的移动作相应的改变,并且泄露损耗变大。通过分析空位缺陷对带隙和泄露损耗的影响,得出在包层比较多的情况下,空位缺陷离PBG-TPCF纤芯越远对PBG-TPCF的影响越小。仿真结果表明空位缺陷在PBG-TPCF包层的第5层时及外围层时对PBG-TPCF的影响将很小以至于可以忽略。

The point defects＇ affect on the band gap and leakage loss of the PBG-type THz photonic crystal fiber （PBG-TPCF） characteristics respectively are studied in this paper. Selected two kinds of point defects make a significant reduction in the band gap, the center frequency shift on varying degrees and the minimum loss of points mobilizing because of the band gap the corresponding movement, and make leakage loss larger. Through the analysis of point defect on the impact of the band-gap and the leakage loss, the result that point defects affect the smaller the more distant from the core of a fiber in the PBG-TPCF with many layers air holes can be gained. This affect can be ignored in the PBG-TPCF with the point defects at the 5th layer or at external layer.