 |
And lastly, from Figure 12 and 13, it is observed that as the silicon core width is made thinner, the effective index will be reduced.
But if the silicon core width is made thicker, it is seen that effective index will eventually increase.
Whereas for core height variations, it is noticed that thicker height will lead to higher effective index.
As seen from both Figures, it is deduced that a width of 500nm is recommended when come in designing waveguide.
This is because when the width of the core is more than 450nm, it is observed that the effective index for higher order (TE1) mode has been gradually increasing.
Thus, the waveguide is said to be multimode and supports not only the fundamental mode but also higher order modes.
At higher order mode, more noise and losses will be obtained.
Thus, it is recommended that the silicon core width is set to be around 500nm to achieve a fundamental mode design which include TE0 and TM0 mode only.
Based on the results, it is precisely presented that a good compromise between effective index and polarization can be achieved with this design. |
IEEE/ICACT20210161 Slide.13
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