光子晶体自准直型光功分器的设计与优化

基于光子晶体的自准直效应,通过在完整光子晶体中引入线缺陷实现光传输方向的改变,并通过改变介质柱的有效折射率设计了一种1×2光功分器。由平面波展开法计算的等频率线图得出自准直光束的传输频率和传输方向。采用有限时域差分法模拟计算器件性能,结果表明所设计的光功分器能有效地实现输入光束能量的均分,且输出能量的比值可通过调节线缺陷介质柱的有效折射率来改变。通过在光场输出位置处引入减反射层有效地使输出效率提高到93.7%。所设计的光功分器体积超微,结构简单,在未来的高集成度的光子集成回路中具有广泛的应用价值。

Design and Optimization of Power Splitter Based on Self-collimation Effect in Photonic Crystals

Based on the self-collimation effect in photonic crystals,the propagation direction of the light is changed by introducing a line defect,and a 1×2 power splitter is presented by changing the effective refraction index of the line defect.The frequency and the direction of the self-collimated beam are achieved by the equal-frequency contours plot calculated by the plane wave expansion method.The simulated results calculated by the finite-difference time-domain method show that the designed power splitter can split the input power efficiently and equally.And the output power ratio is changeable by varying the effective refraction index of the rods.Moreover,the output efficiency of the device is greatly improved to 93.7% by adding antireflection layers at the place of the output positions of light.The power splitter is ultra compact,with a simpler structure,has an extensive application for usage in high-density optical integrated circuits.