Effect of periodicity on optical forces between a one-dimensional periodic photonic crystal waveguide and an underlying substrate

We numerically investigate the attractive optical force between a suspended one-dimensional periodic photonic crystal waveguide and underlying substrate in a silicon-on-insulator platform. We show that the optical force is enhanced by designing the waveguide cross section to make the mode approach the band edge or substrate light line. We show that for periodic waveguides, the optical force is nonmonotonic with waveguide-substrate separation. This effect may enable the design of compact, integrated optical power limiters. (C) 2010 American Institute of Physics. [doi:10.1063/1.3493658]