Monolithic 1 × 8 DWDM Silicon Optical Transmitter Using an Arrayed-Waveguide Grating and Electro-Absorption...

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• High-density wavelength-division multiplexing (DWDM) is crucial for data center interconnects.
• Silicon photonics offers a promising platform for integrated optical transmitters.
• Existing solutions often face challenges in terms of integration and cost.

Purpose of the Study:

• To develop an eight-channel monolithic silicon optical transmitter.
• To utilize silicon electro-absorption modulators (EAMs) for dense wavelength division multiplexing (DWDM).
• To assess the feasibility for intra-data-center interconnects and CMOS compatibility.

Main Methods:

• Design and fabrication of a monolithic transmitter integrating a 1x8 silicon arrayed-waveguide grating (AWG) and eight EAMs.
• Employing free-carrier injection by Schottky junctions for EAM operation.
• Utilizing a single broadband light source for generating eight DWDM channels.

Main Results:

• Successful generation of eight-channel DWDM outputs with 1.33 nm channel spacing in the C-band.
• Achieved over 3 dB modulation depth per channel at 6 V peak-to-peak.
• Demonstrated a compact transmitter footprint (5.41 x 2.84 mm^2).

Conclusions:

• The proposed silicon EAM-based DWDM transmitter is feasible for intra-data-center interconnects.
• The monolithic design offers advantages for heterogeneous integration and CMOS compatibility.
• This technology paves the way for cost-effective and high-performance optical interconnects in data centers.