Fig. 3
From: Tunable narrow-band single-channel add-drop integrated optical filter with ultrawide FSR
FSR-free condition analysis. Contour maps of a the stopband of Bragg grating Δλsb, b the FSRFP of F-P cavity, and c the ratio R (R = Δλsb/ FSRFP) as functions of Λ and d. Waveguide width d and Lc are 0.5 μm and 0 μm. d Simulations of the ratio R as a function of Lc and d. Waveguide width d and Λ are 0.5 μm and 316 nm. The dashed white and blue contour lines in c and d represent the value of R = 1 and R = 2, respectively. The pitch number of the Bragg grating and the tapered grating are 150 and 5