High modulation efficiency and large bandwidth thin-film lithium niobate modulator for visible light

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Integrated photonics is crucial for advanced optical systems.
• Modulation of visible light on integrated platforms, especially lithium niobate, presents significant challenges.
• Existing solutions often lack compactness or sufficient bandwidth.

Purpose of the Study:

• To experimentally demonstrate an integrated visible light modulator operating at 532 nm.
• To showcase the capabilities of the thin-film lithium niobate platform for visible light applications.
• To provide a compact and high-bandwidth solution for integrated visible wavelength modulation.

Main Methods:

• Fabrication of an integrated modulator on a thin-film lithium niobate platform.
• Characterization of waveguide propagation loss (2.2 dB/mm) and fiber coupling loss (5 dB).
• Measurement of the modulator's voltage-length product (1.1 V·cm) and electro-optic bandwidth (-1.59 dB roll-off at 25 GHz).

Main Results:

• Successful demonstration of an integrated visible light modulator at 532 nm.
• Achieved a low voltage-length product of 1.1 V·cm.
• Exhibited a large electro-optic bandwidth with a roll-off of -1.59 dB at 25 GHz for a 3.3 mm device.

Conclusions:

• The thin-film lithium niobate platform is suitable for integrated visible light modulation.
• The fabricated modulator offers a compact and large-bandwidth solution.
• This work enables future development of small-form-factor integrated systems operating at visible wavelengths.