Compact unidirectional waveguide grating emitter with enhanced wavelength sensitivity based on the hybrid plasmonic...

Area of Science:

• Photonics and Optical Engineering
• Nanotechnology
• Antenna Design

Background:

• Waveguide grating antennas are crucial for beam-steering in optical arrays, but traditional designs have limited tuning ranges due to low grating dispersion.
• Enhancing wavelength sensitivity is key to improving the performance of these beam-steering devices.

Purpose of the Study:

• To propose a compact silicon grating waveguide antenna array with enhanced wavelength sensitivity.
• To improve the tuning range and efficiency of optical beam-steering devices.

Main Methods:

• Introducing a periodically modulated hybrid plasmonic mode supported by hybrid plasmonic waveguides (HPWs).
• Utilizing silicon waveguides with periodic subwavelength silver strips for HPWs.
• Depositing silicon emitting segments above HPWs to convert guided to radiated waves.
• Arranging HPWs horizontally to act as a reflector for unidirectional emission.

Main Results:

• Achieved a wavelength-tuning efficiency of up to 0.3°/nm over a 1500–1600 nm wavelength range.
• Demonstrated significant improvement in tuning efficiency compared to traditional designs.
• Obtained an average upward emissivity exceeding 80%, with a maximum of 89% within a 100 nm bandwidth.

Conclusions:

• The proposed compact antenna array offers an effective solution for large-scale integrated optical beam-steering.
• Enhanced wavelength sensitivity and high emissivity are key advantages of the new design.
• This work paves the way for high-tuning-efficiency optical beam-steering devices.