Ultra-compact 8 × 8 strictly-non-blocking Si-wire PILOSS switch.

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Semiconductor Devices

Background:

• Optical switching is crucial for high-speed data communication networks.
• Existing optical switches often face challenges with size, insertion loss, and crosstalk.
• Silicon photonics offers a promising platform for miniaturized and efficient optical devices.

Purpose of the Study:

• To design and fabricate a novel 8x8 matrix switch with path-independent insertion loss (PILOSS).
• To achieve a record-small footprint for optical matrix switches.
• To demonstrate the performance of the PILOSS switch with high-speed digital-coherent signals.

Main Methods:

• Utilized Si-wire waveguides for device fabrication.
• Integrated 64 thermo-optic Mach-Zehnder (MZ) switches.
• Incorporated 49 low-crosstalk directional coupler intersections.
• Employed directional couplers for low-loss switch composition.

Main Results:

• Achieved a record-small footprint of 3.5 × 2.4 mm² for the 8x8 PILOSS switch.
• Demonstrated path-independent insertion loss characteristics.
• Successfully switched a digital-coherent 43-Gbps Quadrature Phase Shift Keying (QPSK) signal.
• Exhibited low crosstalk at the integrated intersections.

Conclusions:

• The developed Si-wire waveguide PILOSS switch offers a highly compact and efficient solution for optical switching.
• The device architecture enables low loss and low crosstalk, suitable for advanced optical networks.
• Successful demonstration with high-speed signals validates its potential for future communication systems.