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arXiv · 1503.01914

Low-loss mode converter for coupling light into slotted photonic crystal waveguide

Xingyu Zhang·Harish Subbaraman·Amir Hosseini·Zeyu Pan·Hai Yan·Chi-jui Chung·Ray T. Chen
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Abstract

We design, fabricate and experimentally demonstrate a highly efficient adiabatic mode converter for coupling light into a silicon slot waveguide with a slot width as large as 320nm. This strip-to-slot mode converter is optimized to provide a measured insertion loss as low as 0.08dB. Our mode converter provides 0.1dB lower loss compared to a conventional V-shape mode converter. This mode converter is used to couple light into and out of a 320nm slot photonic crystal waveguide, and it is experimentally shown to improve the coupling efficiency up to 3.5dB compared to the V-shape mode converter, over the slow-light wavelength region.

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Xingyu Zhang, Harish Subbaraman, Amir Hosseini, Zeyu Pan, Hai Yan, Chi-jui Chung, Ray T. Chen. 2015-03-06. Low-loss mode converter for coupling light into slotted photonic crystal waveguide. https://doi.org/10.1117/12.2076499

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