Broadband optical modulator of fiber type

Area of Science:

• Photonics and Optical Engineering
• Materials Science
• Electrical Engineering

Background:

• Lithium niobate (LiNbO3) is a key material for electro-optic modulators.
• Achieving simultaneous velocity and impedance matching is crucial for high-performance modulators.
• Existing designs often face trade-offs between these parameters.

Purpose of the Study:

• To propose and design a novel fiber-type lithium niobate optical modulator.
• To achieve simultaneous velocity and impedance matching in the modulator design.
• To optimize the modulator for low operating voltage and high bandwidth.

Main Methods:

• Utilized the finite element method (FEM) for modulator analysis and design.
• Focused on achieving velocity matching between optical and electrical waves.
• Ensured characteristic impedance matching for efficient signal transmission.

Main Results:

• The designed modulator achieved simultaneous velocity and impedance matching.
• A low half-wave voltage of 2.28V was obtained.
• A broad 3dB optical bandwidth of 116.3GHz was demonstrated.
• A characteristic impedance of 50.67Ω was achieved at 1.5µm wavelength.

Conclusions:

• The proposed fiber-type lithium niobate optical modulator design is effective.
• Simultaneous velocity and impedance matching is feasible and beneficial.
• The modulator exhibits excellent performance metrics for optical communication applications.