Different-mode power splitters based on a multi-dimension direct-binary-search algorithm.

Area of Science:

• Photonics and optical engineering
• Integrated optics
• Waveguide devices

Background:

• Efficient optical signal splitting is crucial for various photonic applications.
• Existing power splitters often face limitations in mode control and fabrication complexity.
• Developing devices that can handle multiple optical modes is an ongoing challenge.

Purpose of the Study:

• To design, fabricate, and characterize a novel different-mode (waveguide-connected) power splitter ((W)PS).
• To achieve simultaneous generation of fundamental transverse electric (TE0) and TE1 modes with a 1:1 output balance.
• To optimize device performance, fabrication robustness, and reduce design time.

Main Methods:

• Development of a novel multi-dimension direct-binary-search algorithm.
• Systematic search across state, rotation, shape, and size dimensions for parameter optimization.
• Fabrication and characterization of the designed (W)PS using standard photonic fabrication techniques.

Main Results:

• The (W)PS successfully generates TE0 and TE1 modes with a 1:1 output balance.
• Significantly shortened adiabatic taper length compared to traditional power splitters (PS).
• Measured insertion loss < 0.9 dB and crosstalk < -17.8 dB across 1540-1560 nm.
• Demonstrated potential for extension to multiple output ports with tunable tap couplers.

Conclusions:

• The novel multi-dimension search algorithm enables efficient design of complex photonic devices like the (W)PS.
• The developed (W)PS offers superior performance in mode splitting and reduced footprint.
• The device architecture is adaptable for advanced multi-port and multi-mode optical signal routing.