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Published on: February 27, 2019
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Asymmetric dual-core liquid crystal channel-based tunable mode converter
Mohamed Saleh Mohamed Esmail1, Mohamed Farhat O Hameed2,3, Salah S A Obayya4
1Basic Science Department, Faculty of Engineering, Misr University for Science and Technology, Giza, 12588, Egypt.
Scientific Reports
|March 4, 2024
Summary
This study presents a compact silicon mode converter using an asymmetric dual channel waveguide infiltrated with liquid crystal for temperature tunability. The device achieves efficient wavelength selectivity and low crosstalk for integrated photonic circuits.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
- Integrated Optics
Background:
- Mode converters are crucial components in integrated photonic circuits for manipulating light.
- Achieving compact, efficient, and tunable mode converters remains a significant challenge.
Purpose of the Study:
- To design and analyze a novel higher order-to-fundamental mode converter.
- To incorporate temperature tunability using nematic liquid crystal (NLC).
- To achieve a compact device with good wavelength selectivity and low crosstalk.
Main Methods:
- Utilized an asymmetric dual channel waveguide (ADC-WG) on silicon.
- Employed the full vectorial finite difference method (FVFDM) for modal analysis.
- Investigated structural parameters and material optical characteristics.
Main Results:
- Presented a compact mode converter with a device length (LD) of ~482.31 μm.
- Achieved a low crosstalk of -19.86 dB at 1.55 μm.
- Demonstrated temperature tunability between 20 and 35 °C, showing consistent coupling length (LC) with varying phase matching wavelengths (λPMW).
Conclusions:
- The proposed asymmetric dual channel waveguide mode converter offers a compact and tunable solution.
- The integration of NLC provides effective thermal tunability for wavelength selectivity.
- The device is suitable for applications in integrated photonic circuits.
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