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Related Experiment Video

Updated: Jan 23, 2026

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation

Published on: February 25, 2017

Ultrahigh-efficiency apodized grating coupler using fully etched photonic crystals.

Yunhong Ding¹, Haiyan Ou, Christophe Peucheret

¹Department of Photonics Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark. yudin@fotonik.dtu.dk

|August 2, 2013

Summary

We developed an efficient method to design apodized grating couplers for seamless silicon chip and fiber optic integration. This technique achieves high coupling efficiency and a wide bandwidth, minimizing signal loss in photonic devices.

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Area of Science:

Photonics and Optical Engineering
Materials Science

Background:

Efficient light coupling between optical fibers and silicon photonic integrated circuits (PICs) is crucial for advanced applications.
Existing grating coupler designs often face challenges with coupling efficiency, bandwidth, and fabrication complexity.

Purpose of the Study:

To design and demonstrate an efficient apodized grating coupler with a Gaussian output profile.
To achieve high coupling efficiency and a wide bandwidth for fiber-to-chip communication.

Main Methods:

Design of an apodized grating coupler utilizing fully etched photonic crystal holes on a silicon-on-insulator (SOI) platform.
Fabrication in a single step of lithography and etching for streamlined manufacturing.

Main Results:

Experimental measurement of ultralow coupling loss of -1.74 dB, corresponding to 67% coupling efficiency.
Achieved a 3 dB bandwidth of 60 nm, indicating robust performance over a range of wavelengths.

Conclusions:

The proposed apodized grating coupler offers a highly efficient and practical solution for interfacing standard single mode fibers with silicon chips.
The single-step fabrication process simplifies manufacturing, paving the way for scalable photonic integration.