Cascaded subarray design and control method for power efficient, thermal crosstalk optimized optical phased array.

Area of Science:

• Photonics
• Integrated Optics
• Optical Phased Arrays

Background:

• Thermo-optic phase shifters (TOPSs) are crucial for silicon photonic integrated optical phased arrays (OPAs).
• High power consumption and thermal crosstalk in TOPSs limit OPA performance and control accuracy.
• Existing methods struggle to balance response speed, power usage, and thermal management.

Purpose of the Study:

• To propose and validate a combined subarray design and array control method to mitigate thermal crosstalk in silicon photonic OPAs.
• To reduce power consumption and improve the thermal management of TOPSs within dense OPA architectures.
• To enhance the overall control accuracy and efficiency of large-scale optical phased arrays.

Main Methods:

• A combined approach involving subarray design in the optical power distribution network and an optimized array control method.
• Thermal simulations were performed on generic OPA models to analyze thermal behavior.
• Fabrication and experimental validation of a 4x4 OPA prototype with three-level cascaded subarrays.

Main Results:

• The proposed method reduced average total power consumption by 31%.
• Maximum local temperature within the OPA was decreased by 18.4%.
• Significant mitigation of thermal crosstalk was achieved, improving control accuracy.

Conclusions:

• The combined subarray design and array control method effectively addresses thermal crosstalk and power consumption challenges in silicon photonic OPAs.
• This approach offers a viable solution for enhancing the performance and scalability of optical phased array systems.
• The demonstrated prototype validates the practical applicability and benefits of the proposed thermal management strategy.