A compact thermo-optical multimode-interference silicon-based 1 × 4 nano-photonic switch

Area of Science:

• Photonics
• Nanotechnology
• Optical Engineering

Background:

• Multimode interference (MMI) devices are crucial for optical signal management.
• Silicon photonics offers a scalable platform for integrated optical circuits.
• Thermo-optical effects provide a viable mechanism for active control in photonic devices.

Purpose of the Study:

• To demonstrate an ultra-compact 1x4 nano-photonic switch.
• To leverage silicon thermo-optical effects for switch operation.
• To characterize the performance of MMI-based photonic switches.

Main Methods:

• Fabrication of an MMI-based 1x4 photonic switch on a silicon-on-insulator (SOI) platform.
• Systematic characterization of constituent components: 1x4 power splitter, 4x4 MMI coupler, and thermo-optical heaters.
• Development of a model to estimate power consumption and analyze MMI coupler imbalance effects.

Main Results:

• Achieved an average insertion loss of 1.7 dB across different switching states at 1550 nm.
• Demonstrated a transmission imbalance of 1.05 dB.
• Reported a worst-case extinction ratio of 11.48 dB and crosstalk of -11.38 dB.

Conclusions:

• The developed MMI-based nano-photonic switch exhibits promising performance for optical switching applications.
• The silicon thermo-optical effect is effectively utilized for compact and efficient photonic switching.
• The established model provides valuable insights into power consumption and performance limitations.