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arXiv · 2010.03435

Fabrication Development of a Large Area Grating for Out of Plane Beam Coupling

Jonathan Trisno·Tong Hua Lee·Parvathi Nair S.·You Sin Tan·Ray J. H. Ng·Yingyan Huang·Seng Tiong Ho·Joel K. W. Yang
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Abstract

We develop a single-layer waveguide surface grating structure to vertically couple near infrared (NIR) light at ~1.55 um wavelength from a large area (~100 um length scale) Si waveguide on a Silicon-On-Insulator (SOI) substrates to free-space for high-power laser applications. Our design approach is based on the optimization of local emission angles and the out-coupling intensities. Simulation results show that a focal spot with a 1/e2 width of 3.82 um can be achieved at the desired focal position, with 33% (-4.81 dB) simulated source to free-space focusing efficiency, while initial measurements show an efficiency of 22% (-6.58 dB).

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Jonathan Trisno, Tong Hua Lee, Parvathi Nair S., You Sin Tan, Ray J. H. Ng, Yingyan Huang, Seng Tiong Ho, Joel K. W. Yang. 2020-10-07. Fabrication Development of a Large Area Grating for Out of Plane Beam Coupling. https://arxiv.org/abs/2010.03435

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