  Optofluidic sensors based on highly dispersive two-dimensional photonic
crystal waveguides are theoretically studied. Results show that these
structures are strongly sensitive to the refractive index of the infiltrated
liquid (nl), which is used to tune dispersion of the photonic crystal
waveguide. Waveguide mode-gap edge shifts about 1.2 nm for dnl=0.002. The
shifts can be explained well by band structure theory combined with first-order
perturbation theory. These devices are potentially interesting for chemical
sensing applications.
