Inverse-designed arbitrary-input and ultra-compact 1 × N power splitters based on high symmetric structure

Area of Science:

• Photonics and Optical Engineering
• Integrated Optics
• Nanophotonics

Background:

• Optical power splitters are fundamental components in photonic integrated circuits.
• Existing designs often have limitations in terms of size, input port flexibility, and bandwidth.

Purpose of the Study:

• To propose and design arbitrary-input, ultra-compact 1x2 and 1x3 optical power splitters.
• To leverage inverse design methods for optimizing device performance and structure.
• To investigate the performance and fabrication tolerances of the proposed power splitters.

Main Methods:

• Utilizing inverse design methodology for device optimization.
• Employing 3D finite-difference time-domain (FDTD) simulations for performance analysis.
• Analyzing device performance across a range of wavelengths and evaluating fabrication tolerances.

Main Results:

• Designed ultra-compact 1x2 and 1x3 power splitters with regular hexagonal and octagonal structures.
• Achieved low excess loss (<1.5 dB for 1x2, <1.9 dB for 1x3) over a 100 nm bandwidth.
• Demonstrated low crosstalk (< -15.5 dB for 1x3) at 1550 nm.
• Investigated the impact of fabrication errors on device performance.

Conclusions:

• The proposed inverse-designed power splitters offer arbitrary input functionality and excellent performance.
• These ultra-compact devices are suitable for advanced integrated photonic applications.
• The designs exhibit robustness to fabrication errors, paving the way for practical implementation.