Terahertz broadband spoof surface plasmon polaritons using high-order mode developed from ultra-compact split-ring...

Area of Science:

• Electromagnetics and Photonics
• Materials Science

Background:

• Terahertz (THz) technology requires efficient waveguiding structures.
• Traditional spoof surface plasmon polariton (SSPP) structures face limitations in size and bandwidth for high-order modes.
• Miniaturization is crucial for integrated circuit applications.

Purpose of the Study:

• To propose and demonstrate an ultra-compact structure for broadband THz spoof surface plasmon polaritons (SSPPs).
• To achieve significant size reduction while maintaining high-order mode propagation characteristics.
• To explore the potential for plasmonic integrated circuits at microwave and THz frequencies.

Main Methods:

• Design of ultra-compact split-ring grooves for SSPP generation.
• Numerical simulation and analysis of high-order mode propagation and confinement.
• Fabrication and measurement of a microwave prototype to validate the design.
• Characterization of low-pass filtering performance.

Main Results:

• Demonstrated highly concentrated high-order mode propagation with reduced radiation loss.
• Achieved an 83.5% size reduction compared to traditional grounded SSPP structures.
• Microwave prototype exhibited good low-pass filtering (reflection < -10 dB up to 13 GHz).
• Insertion losses ranged from 0.5 dB to 4.5 dB.

Conclusions:

• The proposed ultra-compact split-ring groove structure enables efficient THz broadband high-order SSPP propagation.
• This work presents the first demonstration of THz high-order broadband SSPP propagation.
• The structure offers significant miniaturization potential for plasmonic integrated circuits at microwave/THz frequencies.