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arXiv · 1401.4800

High performance nanophotonic circuits based on partially buried horizontal slot waveguides

Chi Xiong·Wolfram H. P. Pernice·Mo Li·Hong X. Tang
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Abstract

We present a novel platform to construct high-performance nanophotonic devices in low refractive index dielectric films at telecoms wavelengths. The formation of horizontal slots by PECVD deposition of high index amorphous silicon provides a convenient and low-cost way to tailor nanophotonic devices to application needs. Low propagation loss of less than 2 dB/cm is obtained allowing us to fabricate optical resonators with measured high optical quality factors exceeding 10^5. We design and experimentally demonstrate on-chip grating couplers to efficiently couple light into integrated circuitry with coupling loss of 4 dB and optical bandwidth exceeding 110 nm. The entire on-chip circuitry consisting of input/output couplers, Mach-Zehnder interferometers with high extinction ratio and ring, racetrack resonators are designed, fabricated and characterized.

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Chi Xiong, Wolfram H. P. Pernice, Mo Li, Hong X. Tang. 2014-01-20. High performance nanophotonic circuits based on partially buried horizontal slot waveguides. https://doi.org/10.1364/oe.18.020690

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