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Demonstration of Spin-Multiplexed and Direction-Multiplexed All-Dielectric Visible Metaholograms
Published on: September 25, 2020
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Efficient 3D silicon mode (de)multiplexer based on a sidewall-aligned vertical coupler
Applied Optics
|July 17, 2020
Summary
A novel 3D mode (de)multiplexer utilizing a sidewall-aligned vertical coupler achieves compact size and low crosstalk. This device enhances functionality and integration for mode division multiplexing (MDM) systems.
Area of Science:
- Photonics and optical engineering
- Integrated optics
- Waveguide devices
Background:
- Mode division multiplexing (MDM) systems offer increased data capacity by utilizing different spatial modes.
- Efficient mode (de)multiplexers are crucial for realizing practical MDM systems.
- Existing designs often face challenges with size, crosstalk, and bandwidth.
Purpose of the Study:
- To propose and optimize an efficient three-dimensional (3D) mode (de)multiplexer (DeMUX).
- To investigate the performance of a novel dual-waveguide 3D-coupler architecture.
- To demonstrate enhanced functionality and integration capabilities for MDM systems.
Main Methods:
- Utilized a dual-waveguide 3D-coupler with vertically aligned silicon and poly-silicon waveguides.
- Employed the full-vectorial finite element method (FEM) for analysis.
- Applied the 3D full-vectorial finite difference time domain (FDTD) method for performance evaluation.
Main Results:
- Achieved a compact coupling length of 6.88 µm.
- Demonstrated excellent mode crosstalk of -30.04 dB.
- Obtained a low insertion loss of 0.02 dB.
- Reported an ultra-broad 1 dB bandwidth of 300 nm.
Conclusions:
- The proposed 3D mode (De)MUX based on a sidewall-aligned vertical coupler is highly efficient.
- The device shows significant potential for advancing MDM systems.
- This design can lead to increased functionality and integration in optical communication networks.
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