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In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx
Published on: May 13, 2020
Polarization-insensitive subwavelength sharp bends in asymmetric metal/multi-insulator configuration
Yin-Jung Chang1, You-Chang Liu
1Department of Optics and Photonics, National Central University, Jhongli, 32001, Taiwan. yjchang@ncu.edu.tw
Optics Express
|March 4, 2011
Summary
Researchers developed a novel silicon waveguide bend using metal and insulators. This design minimizes signal loss for both TE and TM modes, enhancing optical device efficiency.
Area of Science:
- Photonics
- Nanotechnology
- Materials Science
Background:
- Waveguide bends are crucial components in integrated photonic circuits.
- Achieving low loss in sharp bends, especially for TM modes, remains a challenge.
Purpose of the Study:
- To design and analyze a novel silicon-based sharp waveguide bend.
- To investigate the electromagnetic behavior of TE and TM modes in an asymmetric metal/multi-insulator configuration.
- To derive general design rules for efficient waveguide bends.
Main Methods:
- Rigorous electromagnetic calculations for TE and TM modes.
- Numerical simulations to determine insertion losses and bending characteristics.
- Analysis of structure-enabled photonic-plasmonic mode conversions.
Main Results:
- Achieved low insertion losses: < 0.085 dB for TE and < 0.229 dB for TM modes.
- Introduced a low-index layer to enhance performance.
- Demonstrated that bending length primarily impacts TE modes.
- Observed structure-enabled mode conversions increasing TM mode confinement.
Conclusions:
- The proposed silicon waveguide bend offers high transmission efficiency for both TE and TM modes.
- The design rules derived are applicable for optimizing integrated photonic devices.
- Plasmonic mode conversion effectively carries significant power along the bend.
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