Optical response of high-order band gap in one-dimensional photonic crystal applying in-plane integration

A new broadband filter, based on the high-order band gap in one-dimensional photonic crystal (PCs) of the form Si∣air∣Si∣air∣Si∣air∣Si∣air∣Si∣air∣Si, has been designed by the plane wave expansion method (PWEM) and transfer matrix method (TMM) and fabricated by lithography. The optical response of this filter to normal-incident and oblique-incident light proves that utilizing the high-order band gaps of PCs is an efficient method to lower the difficulties of fabricating PCs, increase the etching depth of semiconductor materials, and reduce the coupling loss at the interface between optical fibers and PC device.