Application of Tunablef Self-collimation in LCD Photonic Crystals

Photonic crystals with liquid-crystlal materials are extensively studied for their tunabilities. However, until now the studies mainly focused on the tunable photonic band gap properties. In this article, the tunable self-collimation in liquid-crystal-filled photonic crystals is discussed in detail. The impact of the twist angle of liquid crystals on the self-collimating frequencies is presented by using the plane wave expansion method. Moreover, the light propagation in the photonic crystal is simulated with the finite-difference time-domain method. The simulations show that the self-collimating frequencies are tunable by changing the liquid-crystal twist angle so that the self-collimating photonic crystals can be applied in different frequency bands.