Photonic-Crystal Band-pass Resonant Filters Design Using the Two-dimensional FDTD Method

Recently, band-pass photonic crystal filters have attracted great attention due to their important applications in the fields of optical interconnection network and ultrahigh speed information processing. In this paper we propose the design of a new type of photonic crystal band-pass resonant filters realized in onemissing-row waveguide by decreasing proper defects along the waveguide with broadband acceptable bandwidth. Two types of photonic crystal band-pass filters are utilized and optimized using the Two-dimensional finite-difference time-domain (FDTD) technique. The first one is based on the Fabry-Pérot cavities and in the second one a cavity is introduced in the middle by omitting two neighboring air holes in waveguide. Numerical results show that a band [1.47 μm-1.57 μm] around 1.55μm is transmitted with a maximum transmission of about 68% and as a result wide band-pass filters are designed.