SiN/Si double-layer platform for ultralow-crosstalk multiport optical switches.

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Optical switches are crucial for high-speed data transmission.
• Minimizing crosstalk is essential for maintaining signal integrity in complex optical networks.
• Existing platforms face challenges in achieving ultralow crosstalk for large-scale integration.

Purpose of the Study:

• To demonstrate a double-layer platform for ultralow-crosstalk multiport optical switches.
• To evaluate the performance of silicon nitride and silicon materials in this configuration.
• To assess the scalability of the proposed platform for larger switch arrays.

Main Methods:

• Experimental fabrication of a double-layer platform using silicon nitride and silicon.
• Integration of a silicon nitride overpass with a 1.5 µm gap.
• Characterization of optical switch performance, focusing on crosstalk levels across the C-band.
• Testing of 4x4, 16x16, and a 32x32 passive test device.

Main Results:

• Achieved crosstalk below -50 dB for 4x4 switches and -45 dB for 16x16 switches in the C-band.
• Demonstrated feasibility of worst-case crosstalk below -50 dB for a 32x32 passive test device.
• The silicon nitride overpass design effectively suppressed signal leakage.

Conclusions:

• The double-layer silicon nitride and silicon platform enables ultralow-crosstalk multiport optical switches.
• The platform shows excellent scalability for large-scale optical switching applications.
• This technology is promising for advancing high-performance optical communication systems.