Coplanar-waveguide-based silicon Mach-Zehnder modulator using a meandering optical waveguide and alternating-side PN...

Area of Science:

• Photonics
• Electrical Engineering
• Materials Science

Background:

• Silicon photonics enables integrated optical circuits.
• Mach-Zehnder modulators (MZMs) are key components for optical signal modulation.
• Achieving high electro-optic (EO) bandwidth and low driving voltage is crucial for high-speed optical communication.

Purpose of the Study:

• To develop a silicon Mach-Zehnder modulator with enhanced electro-optic (EO) bandwidth and low driving voltage.
• To suppress signal distortion caused by parasitic slot-line modes in silicon modulators.
• To optimize the electrode structure for improved modulator performance.

Main Methods:

• Utilized a coplanar waveguide transmission-line electrode structure.
• Incorporated a meandering optical waveguide design.
• Employed alternating-side PN junction loading of electrodes.

Main Results:

• Demonstrated a silicon Mach-Zehnder modulator (MZM).
• Achieved a π-phase-shift voltage (Vπ) of 4.5 V.
• Obtained an electro-optic (EO) 3 dB bandwidth of approximately 20 GHz for a 5 mm phase shifter.

Conclusions:

• The novel electrode structure effectively suppresses parasitic slot-line modes, reducing signal distortion.
• The demonstrated silicon MZM offers a low Vπ and high EO bandwidth, competitive with existing technologies.
• This work contributes to the advancement of high-performance silicon modulators for optical communication systems.