【摘要】 通过改变最内层两排空气孔的半径,研究了Ge20Sb15Se65硫基光子晶体平板波导的宽带慢光特性。利用三维平面波展开法,通过计算得到波导的能带结构、群折射率和色散,并分析了它们与内层空气孔半径大小的关系。同时优化第一层和第二层空气孔的半径大小,得到了群速度色散为零的对称型硫系光子晶体波导结构,并在20%的变化范围内获得大小分别为125、40和18的群折射率,对应通信波长处的带宽分别为1.7、5.6、9.7 nm,并讨论了折射率对光子晶体波导慢光性能的影响。并为高非线性、低色散的宽带慢光硫基光子晶体平板波导器件的设计及制备提供了理论基础。更多还原

【Abstract】 The slow light propagation in a Ge20Sb15Se65 chalcogenide photonic crystal slab waveguide(PCSW) of air holes is investigated via the three-dimensional plane wave expansion(PWE) method. By perturbing the first two rows of air holes adjacent to the waveguide core, the group index, the bandwidth and the dispersion can be tuned effectively, and the symmetric chalcogenide photonic crystal slab waveguides with zero dispersion are obtained. The slow lights with the group indices of 125, 40, and 18 are demonstrated, with the bandwidths of 1.7,5.6 and 9.7 nm, respectively. Finally, the effects of refractive index of chalcogenide materials on the slow light in the photonic crystal slab waveguide are discussed. It shows perfect slow-light properties in chalcogenide PCSWs and can be used as an affordable reference for further research in chalcogenide photonic crystal waveguide devices.更多还原