Figure 5

Precise adjustment of the channel wavelength positions of the fabricated device to the originally designed. Transmission spectra of the originally designed triple-defect device operating within the second SB ( m = 2, Table 1) (black line) and of the fabricated device with structural deviations of ± δ d_Si = 20 nm = 5.6% ( m = 2, Table 2) (red line). (a) The refractive index of all cavities $n_{\text{def}}^{(\mathbf{2}\mathbf{,}\mathbf{4}\mathbf{,}\mathbf{6})}=1.63$. (b) Precise adjustment of the edge channel wavelength positions of the fabricated device to match those in the original design by decreasing the refractive index to $n_{\text{def}}^{(\mathbf{2}\mathbf{,}\mathbf{4}\mathbf{,}\mathbf{6})}=1.60$. (c) Final adjustment of the central channel with $n_{\text{def}}^{\left(\mathbf{4}\right)}-∆n=1.60-0.01$ and $n_{\text{def}}^{\left(\mathbf{4}\right)}-∆n=1.60-0.01$.