Scalable selective high order mode pass filter architecture with asymmetric directional couplers

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Optical Communication Systems

Background:

• Mode division multiplexing (MDM) is a key technology for increasing optical network capacity.
• Existing mode filters often lack scalability and design flexibility.
• Efficient and selective filtering of optical modes is essential for advanced communication systems.

Purpose of the Study:

• To propose and demonstrate a novel, scalable architecture for selective mode filters.
• To enable the passage of desired high-order optical modes while suppressing unwanted modes.
• To showcase the design flexibility for filtering multiple optical modes.

Main Methods:

• Utilizing an asymmetric directional coupler structure for mode filtering.
• Designing and fabricating a three-mode selective filter as a proof of concept.
• Demonstrating scalability with a four-mode filter design.

Main Results:

• Experimental validation of a three-mode selective filter.
• Demonstration of the proposed structure's scalability for filtering multiple modes.
• Achieved selective passage of high-order modes with suppression of others.

Conclusions:

• The proposed asymmetric directional coupler architecture provides a scalable and flexible solution for selective mode filtering.
• This technology holds significant potential for advanced mode division multiplexing optical networks.
• The design enables precise control over which optical modes are transmitted or blocked.