Compact design of a tunable high-pass filter based on one-dimensional photonic crystal waveguide

In this work, we proposed a compact design of a tunable high-pass filter based on the one-dimensional photonic crystal waveguide. The device design is simple and cut-off wavelength can be tuned by a few geometric parameters. The spectral characteristics of the high-pass filter are calculated for the wavelength range of 1200 nm to 2000 nm. The numerical simulations suggest that the extinction ratio of >22 dB is obtained for the wavelength range lying in the photonic bandgap for the device footprint of 3.4 x 1 μm2. We believe that our findings are useful for the realization of photonic integrated circuit filters with miniaturized footprint.