Manipulating microwaves with ‘spoof’ surface plasmons

Reply to “Comments on “A High-Gain Antenna Consisting of Two Slot Elements With a Space Larger Than a Wavelength””

“…Thus, the electromagnetic fields at these frequencies can only penetrate a skin depth inside the metal that is less than 1 m, but extend many wavelengths into the dielectric region, which means that the field localization to the surface in the dielectric region is almost nonexistent [13]. Therefore, some researchers refer to it as some form of surface currents instead of SPs [13]- [17].…”

“…In this case, the metals would support a kind of surface electromagnetic mode, whose dispersion relation has strong similarities with that of SPs [29]. Thus, this surface mode is often called spoof SPs [29]- [31], designed SPs [15], [17] or SPs-like mode [16], [32]- [34]. That means the existence of SPs (spoof SPs) does not only depend on the strong dispersion of metal anymore, but can be produced by designing the specific patterns in any metal at long wavelengths [15], [17], [29].…”

“…Thus, this surface mode is often called spoof SPs [29]- [31], designed SPs [15], [17] or SPs-like mode [16], [32]- [34]. That means the existence of SPs (spoof SPs) does not only depend on the strong dispersion of metal anymore, but can be produced by designing the specific patterns in any metal at long wavelengths [15], [17], [29]. In the recent review [35] published in 2010, a much wider concept that is surface electromagnetic modes was proposed to explain ET.…”

3-D Numerical Analysis of Smith–Purcell-Based Terahertz Wave Radiation Excited by Effective Surface Plasmon

“…Structured surfaces are created by adding geometric patterns to the metal such as slits, grooves, holes and dielectric layers which in the low-frequency regime they form pseudo-bound states and hence the structure will show SP-like optical responses [17]. At the THz regime, these propagating surface waves are called "mimicking" [18] or "spoof" [19] surface plasmons. THz surface plasmons operate in an intermediate regime, where the interaction between the electromagnetic mode and the plasma of electrons in the metal are stronger than in the microwave range, but weaker than in the infrared region.…”

“…THz surface plasmons operate in an intermediate regime, where the interaction between the electromagnetic mode and the plasma of electrons in the metal are stronger than in the microwave range, but weaker than in the infrared region. In the low frequency regime where the metallic resistivity is extremely low and the interaction between the wave and the electron plasma is weak, surface waves are considered to be plane waves propagating parallel to the interface with very little plasmonic character and propagation distance in the order of hundreds of wavelengths [19]. Subwavelength array of geometric patterns in metallic substrates support a series of cavity resonances (Fabry-Perot-like), where each harmonic of the resonance results in a peak in the transmission spectrum [20].…”