Liu Chen-Yang, Chen Lien-Wen
Opt Express. 2004 Jun 14;12(12):2616-24. doi: 10.1364/opex.12.002616.
Photonic crystals (PCs) have many potential applications because of their ability to control light-wave propagation and because PC-based waveguides may be integrated into optical interferometers. We propose a novel tunable PC waveguide Mach-Zehnder interferometer based on nematic liquid crystals and investigate its interference properties numerically by using the finite-difference time-domain method. We can change the refractive indices of liquid crystals by rotating the directors of the liquid crystals. Then we can control the phase of light propagation in a PC waveguide Mach-Zehnder interferometer. The interference mechanism is a change in the refractive indices of liquid-crystal waveguides. The novel interferometer can be used either as an optically controlled on-off switch or as an amplitude modulator in optical circuits.
光子晶体（PCs）因其能够控制光波传播以及基于PC的波导可集成到光学干涉仪中而具有许多潜在应用。我们提出了一种基于向列型液晶的新型可调谐PC波导马赫-曾德尔干涉仪，并使用时域有限差分法对其干涉特性进行了数值研究。我们可以通过旋转液晶的指向矢来改变液晶的折射率。然后我们可以控制PC波导马赫-曾德尔干涉仪中光传播的相位。干涉机制是液晶波导折射率的变化。这种新型干涉仪既可以用作光控开关，也可以用作光电路中的幅度调制器。
