Related Experiment Video
Updated: Jun 13, 2025
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
21.7K
Investigating orbital angular momentum modes in multimode interference (MMI) waveguides and revealing their mode
Afsoun Soltani1, S Faezeh Mousavi2,3, Zaker Hossein Firouzeh4
1Department of Electrical and Computer Engineering, Isfahan University of Technology, Isfahan, 8415683111, Iran.
Scientific Reports
|September 11, 2024
Summary
This study investigates orbital angular momentum (OAM) modes in multimode interference (MMI) waveguides, finding that input mode waist radius enhances image quality. Wider waveguides decrease self-imaged mode quality, but mode conversion is observed for integrated optical applications.
Area of Science:
- Optics and Photonics
- Integrated Optics
- Waveguide Technology
Background:
- Multimode interference (MMI) waveguides are fundamental components in integrated optical devices.
- Orbital angular momentum (OAM) modes offer unique properties for optical applications.
- Understanding OAM mode propagation in MMI waveguides is crucial for advanced optical systems.
Purpose of the Study:
- To investigate the propagation of OAM modes within MMI waveguides.
- To analyze the impact of key parameters on OAM mode self-imaging.
- To explore the potential for OAM mode manipulation in integrated photonic devices.
Main Methods:
- Simulating OAM mode propagation in MMI waveguides.
- Investigating the effects of waveguide width (W) and input OAM mode waist radius (WR).
- Utilizing Power Overlap Integral (POI) to quantify image quality.
Main Results:
- Increasing WR of input OAM modes significantly enhances POI, improving image quality (e.g., from 86.91% to 98.92%).
- Increasing waveguide width (W) degrades the self-imaged mode quality (e.g., from 98.90% to 85.15%).
- Demonstrated mode conversion between even-order OAM modes with opposite topological charges at the OAM-maintaining length.
Conclusions:
- Optimizing WR and W is critical for high-quality OAM mode self-imaging in MMI waveguides.
- The observed mode conversion offers new possibilities for optical communication systems.
- This research advances the integration of OAM modes into practical photonic devices.
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