Proposal for postfabrication fine-tuning of three-port photonic crystal channel drop filters by means of optofluidic infiltration.

We are proposing a procedure to reconfigure a three-port photonic crystal channel drop filter with two point-defect resonant cavities coupled to a bus and a drop W1-type waveguide, by means of selective optofluidic infiltration. Simulations show that, by selective infiltration of cavities and the air holes of the two parallel line defects that are partially surrounding the bus waveguide of the proposed channel drop filter (CDF), besides fine-tuning of the cavities resonant frequencies to the desired values, one can also fine-tune the CDF phase to an optimum condition for achieving optimum drop efficiency for any given resonant frequency. We have used the 2D finite difference time domain and plane wave method to perform the numerical simulations.