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Dual-layer capacitance-loaded thin-film lithium niobate electro-optic modulator with high modulation efficiency.
Optics Express
|November 14, 2024
Summary
We developed a novel dual-layer electrode for thin film lithium niobate modulators, enhancing modulation efficiency and reducing device length. This innovation lowers fabrication costs for high-performance fiber-optic communication devices.
Area of Science:
- Photonics
- Materials Science
- Electrical Engineering
Background:
- Thin film lithium niobate (TFLN) modulators are crucial for fiber-optic communication, requiring low driving voltage and high bandwidth.
- Current TFLN modulator designs face limitations in modulation efficiency due to waveguide loss from metal absorption, restricting electrode spacing.
- Improving modulation efficiency is key to shorter devices, lower voltage, and reduced fabrication costs.
Purpose of the Study:
- To propose and experimentally validate a novel dual-layer capacitance-loaded electrode structure for TFLN modulators.
- To enhance modulation efficiency while minimizing waveguide absorption loss.
- To achieve reduced device length and lower driving voltage for TFLN modulators.
Main Methods:
- Design of a dual-layer capacitance-loaded electrode structure.
- Integration of the novel electrode structure with TFLN waveguides.
- Experimental characterization of the TFLN modulator performance in the C-band.
Main Results:
- Demonstration of a TFLN modulator with a novel electrode design.
- Achieved a low half-wave voltage of 3.2 V.
- Obtained a modulation length of 5 mm and a 3-dB bandwidth exceeding 67 GHz.
Conclusions:
- The proposed dual-layer capacitance-loaded electrode structure effectively enhances modulation efficiency in TFLN modulators.
- This design overcomes limitations of metal absorption loss, enabling shorter devices and lower driving voltages.
- The demonstrated performance indicates significant potential for cost-effective, high-performance fiber-optic communication.
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