Stacked Waveguide Polarizer With Slots For Extinction Ratio
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current polarizer structures in photonics chips are inefficient in selectively propagating desired optical modes while eliminating unwanted modes, leading to suboptimal performance in terms of extinction ratio and mode filtering.
Innovation Solution
The proposed structure for a polarizer includes a series of waveguide cores with alternating bends and slots, where waveguide cores are laterally aligned with the slots, allowing for enhanced mode separation by embedding dielectric materials to fill gaps between the cores, thereby improving the extinction ratio and mode filtering capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional polarizer structures are used, then the device complexity is low, but the extinction ratio and mode filtering performance are insufficient
Solution Approach 1:
The polarizer is divided into multiple functional sections along the waveguide path: an adiabatic section for mode transformation, a polarizing section with slots for mode separation, and a merging section for recombination. Each section performs a specific function to progressively improve extinction ratio while maintaining manageable complexity through modular design
Solution Approach 2:
Multiple waveguides are nested within a single photonic integrated circuit substrate, with slots positioned between adjacent waveguides. The slots are embedded within the dielectric material that fills the space between waveguide cores, creating a compact nested structure that achieves high extinction ratio without proportionally increasing device footprint
2Reliability
If simple waveguide structures are used, then the manufacturing process is simple, but the mode separation capability is insufficient
Solution Approach 1:
Slots are positioned at specific locations between waveguide cores where the electromagnetic field distribution provides optimal mode separation. The slot dimensions, positions, and orientations are locally optimized to target specific mode pairs (e.g., TE0-TE1 or TM0-TM1), allowing effective mode filtering without requiring complex structures throughout the entire device
Solution Approach 2:
The patent extends the design from two-dimensional waveguide cross-sections to three-dimensional stacked configurations, with waveguides arranged in multiple layers separated by vertical distances. This vertical dimension provides additional degrees of freedom for mode separation, enabling enhanced filtering capability while maintaining planar manufacturing compatibility through standard layer-by-layer fabrication processes
3Reliability
If multiple stacked layers with slots are implemented, then the extinction ratio increases, but the device area increases
Solution Approach 1:
The polarizer employs periodic slot patterns along the waveguide propagation direction, with slots repeated at regular intervals. This periodic structure enhances mode separation through cumulative effect while maintaining a compact longitudinal footprint. The adiabatic sections between slots allow gradual mode transformation, enabling high extinction ratio over a shortened interaction length compared to non-periodic designs
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration effectively increases the extinction ratio for unwanted modes and enhances the transmission of desired modes, improving the overall performance of the polarizer by allowing for increased gap fill and improved mode filtering compared to conventional designs.
Implementation Method 1
waveguide cores with alternating bends and slots, where waveguide cores are laterally aligned with the slots
Implementation Method 2
embedding dielectric materials to fill gaps between the cores, thereby improving the extinction ratio and mode filtering capabilities
Implementation Method 3
embedding dielectric materials to fill gaps between the cores, thereby improving the extinction ratio and mode filtering capabilities
Data Source
AI summary
Structures for a polarizer and methods of forming a structure for a polarizer. A first slotted waveguide component is positioned over a first waveguide core, and a second slotted waveguide component positioned over the first slotted waveguide component. The first slotted waveguide component includes a second waveguide core and a third waveguide core separated by a first slot, and the second slotted waveguide component includes a fourth waveguide core and a fifth waveguide core separated by a second slot. The first waveguide core is laterally aligned with the first slot and the second slot.