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On-chip silicon mode blocking filter employing subwavelength-grating based contra-directional coupler
Optics Express
|January 16, 2019
Summary
Silicon mode blocking filters are demonstrated for mode-division multiplexing (MDM) systems. These filters effectively block unwanted modes like TE0 and TE1 without impacting other signals, achieving low crosstalk.
Area of Science:
- Photonics
- Optical Communications
- Integrated Optics
Background:
- Mode-division multiplexing (MDM) systems require effective mode control.
- Existing methods for mode management can be complex or inefficient.
Purpose of the Study:
- To demonstrate a novel silicon mode blocking filter.
- To achieve selective blocking of specific optical modes in MDM systems.
Main Methods:
- Utilizing a subwavelength grating-based contra-directional coupler.
- Fabricating and experimentally testing silicon photonic devices.
Main Results:
- Demonstrated filters capable of blocking TE0 and TE1 modes.
- Achieved low crosstalk (≤21.0 dB) and insertion losses (≤2.3 dB).
- The filters selectively block undesired modes while preserving others.
Conclusions:
- Subwavelength grating-based contra-directional couplers are effective for mode blocking in silicon photonics.
- The demonstrated filters offer a viable solution for mode management in MDM systems.
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