Meta‐Antennas Based on Spoof Surface Plasmon Polaritons

Spoof surface plasmon polaritons (SSPPs) are a class of electromagnetic surface modes that mimic the behavior of optical surface plasmon polaritons (SPPs) at microwave and terahertz frequencies through engineered subwavelength metallic structures. SSPPs exhibit distinctive physical properties, including tunable dispersion, slow‐wave, strong field confinement, magnetic field adjustability and nonlinear frequency dispersion characteristics, enabling precise controls of electromagnetic waves at subwavelength scales. The limited electromagnetic mode control capabilities of conventional antennas hinder their ability to meet the diverse requirements of systems in complex electromagnetic scenarios. The unique physical properties of SSPPs offer a promising solution to address this limitation. This paper presents a comprehensive review of meta‐antennas based on SSPPs, including low radar cross‐section antennas, beam reconfigurable antennas, miniaturized antennas, high‐gain antennas, and other functional antennas. However, it should be noted that the current approach still faces some challenges including high design complexity, significant losses in terahertz band, and single physical mechanisms of SSPPs. Future development necessitates strategies focused on introducing intelligent design methodologies, overcoming the high‐frequency loss bottleneck, and synergistically leveraging the multiple physical properties of SSPPs. This will maximize their unique advantages, thereby further broadening the performance boundaries of the meta‐antennas.