Dual-polarized nanocrescent antenna designed using efficient optimization techniques

Area of Science:

• Nanophotonics and Plasmonics
• Antenna Engineering
• Optical Communication Systems

Background:

• Existing optical communication systems face limitations in capacity.
• Dual-polarized antennas can enhance capacity through frequency reuse.
• Need for compact, efficient antennas at optical frequencies.

Purpose of the Study:

• Introduce a novel nanocrescent antenna with polarization diversity.
• Optimize antenna dimensions for high performance.
• Enable switching between orthogonal linear polarizations for optical communication.

Main Methods:

• Design of a crescent-shaped patch antenna fed by a coupled strip transmission line.
• Optimization using surrogate kriging models and two optimizers (design-centering and multiobjective particle swarm).
• Sensitivity analysis to identify critical design parameters.

Main Results:

• The optimized antenna operates around 193 THz (1550 nm) with a bandwidth over 30 THz.
• Achieved gain > 5.2 dBi and radiation efficiency > 85% across the working band.
• Demonstrated switching between two orthogonal pure linear polarizations with broadside radiation.

Conclusions:

• The proposed nanocrescent antenna effectively provides polarization diversity.
• The antenna design is suitable for doubling optical communication capacity.
• The compact size (~500nm x 500nm) and high performance are promising for integrated nanophotonics.