High-speed electro-optic modulator with group velocity matching on silicon substrate

Area of Science:

• Photonics and optical communications
• Materials science for electronic devices

Background:

• High-speed electro-optic modulators are essential for advanced analog and digital communication systems.
• Achieving low driving voltage and wide bandwidth in modulators remains a challenge.
• Thin-film lithium niobate (TFLN) on silicon is a promising platform for integrated photonics.

Purpose of the Study:

• To propose and demonstrate a novel electrode structure for high-speed TFLN electro-optic modulators.
• To improve the performance of TFLN modulators by reducing driving voltage and increasing bandwidth.
• To enable advanced analog and digital communication systems through enhanced modulator performance.

Main Methods:

• Design and fabrication of a hybrid-loaded T type-U type traveling-wave electrode structure (TU-TWEs).
• Incorporation of an inductance compensation mechanism within the TU-TWEs.
• Integration of the TFLN modulator on a silicon substrate.

Main Results:

• Demonstration of a high-speed TFLN electro-optic modulator on a silicon substrate.
• Achieved an electro-optic bandwidth greater than 110 GHz.
• Obtained a low half-wave voltage of 1.35 V.

Conclusions:

• The proposed TU-TWEs structure effectively reduces microwave refractive index and the 'slow light' effect.
• The inductance compensation mechanism facilitates velocity matching between light and microwave.
• The demonstrated modulator performance surpasses existing technologies, paving the way for next-generation communication systems.