The effect of changing the position of the inner taper crystals on the coupling efficiency between a silica waveguide and a planar photonic crystal

We propose a novel method to enhance the coupling efficiency between a silica waveguide (SWG) and a planar photonic crystal (PPC) by changing the position of the inner taper crystals. Our results confirm that using extra defects at the interface between the SWG and PPC followed by applying the position change method produce a transmission efficiency of 94.6%.