Related Experiment Video
Updated: May 8, 2026
12:19
Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Dramatic size reduction of waveguide bends on a micron-scale silicon photonic platform
Matteo Cherchi1, Sami Ylinen, Mikko Harjanne
1VTT Technical Research Centre of Finland, Espoo, 02040, Finland. matteo.cherchi@vtt.fi
Optics Express
|August 14, 2013
Summary
We achieved ultra-compact, low-loss optical waveguide bends using Euler spirals. These highly multimodal bends enable unprecedented integration density on semiconductor platforms.
Area of Science:
- Photonics
- Materials Science
- Nanotechnology
Background:
- High index contrast waveguides are crucial for miniaturizing photonic integrated circuits.
- Achieving tight bends in waveguides without significant signal loss remains a major challenge for device integration.
Purpose of the Study:
- To theoretically and experimentally demonstrate ultra-compact, low-loss bends for highly multimodal waveguides.
- To enable higher integration density in photonic devices through advanced waveguide design.
Main Methods:
- Design of waveguide bends using Euler spiral geometry.
- Fabrication of bends on 4 µm thick silicon-on-insulator (SOI) substrates.
- Characterization of bend performance across an ultra-broadband range.
Main Results:
- Demonstrated bends with radii below 10 µm and losses < 0.02 dB/90° for the fundamental mode.
- Achieved 180° bends with 1.27 µm effective radii and 0.09 dB loss.
- Reported the smallest low-loss optical waveguide bends to date.
Conclusions:
- The Euler spiral design enables record-small, low-loss waveguide bends.
- This breakthrough facilitates unprecedented integration density in semiconductor photonic platforms.
- The demonstrated technology is compatible with existing silicon photonic fabrication processes.
