110 GHz, 110 mW hybrid silicon-lithium niobate Mach-Zehnder modulator

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• High-performance electro-optic modulators are crucial for analog optical communications and RF photonic links.
• Existing technologies face limitations in optical power handling and bandwidth.

Purpose of the Study:

• To design and fabricate a novel thin-film lithium niobate (LN) Mach-Zehnder modulator (MZM).
• To achieve high optical power handling capability and high bandwidth in an MZM device.

Main Methods:

• Fabrication of a thin-film LN MZM utilizing hybrid optical modes by bonding LN to silicon photonic circuits.
• Employing tapered silicon waveguides to mitigate optically-generated carriers and enhance optical power handling.
• Characterization of the MZM's bandwidth, optical power handling, Vπ·cm product, and insertion loss.

Main Results:

• The fabricated MZM demonstrates a 3-dB bandwidth exceeding 110 GHz at 1550 nm.
• The device successfully handles a high optical power of 110 mW.
• Achieved a Vπ·cm product of 3.1 V·cm and an on-chip optical insertion loss of 1.8 dB.

Conclusions:

• The developed LN MZM offers a promising solution for high-performance analog optical communications and RF photonic links.
• The hybrid integration approach and waveguide tapering effectively address key performance bottlenecks.