Optimal Design of an Ultrasmall SOI-Based 1 × 8 Flat-Top AWG by Using an MMI

Table 2

Comparison of the four methods.

Methods to flatten spectral response	Crosstalk; (dB)	Insertion loss; (dB)	3 dB passband width; (nm)
Using a symmetrical MMI	−19.54	−5.76	1.28
Using a tapered MMI	−21.4	−5.11	1.3
Using combination of a tapered MMI and input/output tapered waveguide	−21.9	−4.36	1.31
Using combination of a symmetrical MMI and input/output tapered waveguide	−21.5	−4.66	1.3