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Published on: March 19, 2016
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Low-loss and compact arbitrary-order silicon mode converter based on hybrid shape optimization.
Junpeng Liao1, Dongmei Huang2, Yegang Lu1
1Ningbo University, Ningbo, China.
Nanophotonics (Berlin, Germany)
|December 5, 2024
Summary
Researchers developed a hybrid shape optimization method for designing compact, high-performance mode converters (MCs) for mode-division multiplexing (MDM) systems. This new technique enables efficient conversion between multiple TE modes on silicon-on-insulator platforms.
Area of Science:
- Photonics
- Integrated Optics
- Optical Communications
Background:
- Mode converters (MCs) are crucial for mode-division multiplexing (MDM) systems.
- Existing silicon-on-insulator (SOI) based MCs often focus on limited mode conversions.
- There is a need for versatile and high-performance MCs for advanced MDM.
Purpose of the Study:
- To introduce a novel hybrid shape optimization (HSO) method for designing arbitrary-order MCs.
- To achieve compact and high-performance MCs on the SOI platform.
- To enable flexible mode conversion for enhanced MDM versatility.
Main Methods:
- Combined particle swarm optimization (PSO) with adjoint methods for waveguide shape optimization.
- Designed S-bend waveguides for efficient mode conversion.
- Validated the approach by fabricating and testing MCs on the SOI platform.
Main Results:
- Developed 13 μm-long MCs capable of converting between TE0 to TE3 modes.
- Achieved efficient conversion with low insertion losses (<1 dB) and crosstalk (< -15 dB).
- Demonstrated wide operational bandwidths for various TE mode conversions (e.g., 80 nm for TE0-TE1).
Conclusions:
- The HSO method enables the design of arbitrary-order, compact, and high-performance MCs.
- The developed MCs offer robust fabrication tolerances and flexibility for on-chip MDM.
- This advancement significantly enhances the capabilities of integrated photonic devices for future communication systems.
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