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arXiv · 1909.06029

Coupling of a whispering gallery mode to a silicon chip with photonic crystal

Yuyang Zhuang·Hajime Kumazaki·Shun Fujii·Riku Imamura·Nurul Ashikin Binti Daud·Rammaru Ishida·Heming Chen·Takasumi Tanabe
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Abstract

We demonstrate the efficient coupling (99.5%) of a silica whispering gallery mode microresonator directly with a silicon chip by using a silicon photonic crystal waveguide as a coupler. The efficient coupling is attributed to the small effective refractive index difference between the two devices. The large group index of the photonic crystal waveguide mode also contributes to the efficient coupling. A coupling Q of 2.68*10^6 is obtained, which allows us to achieve the critical coupling of a silica whispering gallery mode with an intrinsic Q of close to 10^7 with a Si chip.

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Yuyang Zhuang, Hajime Kumazaki, Shun Fujii, Riku Imamura, Nurul Ashikin Binti Daud, Rammaru Ishida, Heming Chen, Takasumi Tanabe. 2019-09-13. Coupling of a whispering gallery mode to a silicon chip with photonic crystal. https://doi.org/10.1364/ol.44.005731

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