Hyperbolic spoof plasmonic metasurfaces

Abstract

Hyperbolic metasurfaces have recently emerged as a new research frontier because of the unprecedented capabilities to manipulate surface plasmon polaritons (SPPs) and many potential applications. However, thus far, the existence of hyperbolic metasurfaces has neither been observed nor predicted at low frequencies because noble metals cannot support SPPs at longer wavelengths. Here, we propose and experimentally demonstrate spoof plasmonic metasurfaces with a hyperbolic dispersion, where the spoof SPPs propagate on complementary H-shaped, perfectly conducting surfaces at low frequencies. Thus, non-divergent diffractions, negative refraction and dispersion-dependent spin-momentum locking are observed as the spoof SPPs travel over the hyperbolic spoof plasmonic metasurfaces (HSPMs). The HSPMs provide fundamental new platforms to explore the propagation and spin of spoof SPPs. They show great capabilities for designing advanced surface wave devices such as spatial multiplexers, focusing and imaging devices, planar hyperlenses, and dispersion-dependent directional couplers, at both microwave and terahertz frequencies.

Infrared hyperbolic metasurface based on nanostructured van der Waals materials

“…4A reveal the wavefronts of in-plane hyperbolic polaritons. Figure 4c also verifies the large polariton wavevectors k achieved with our HMS (for example, = ( 2 + 2 ) 0.5 > 20k0 at = 1425 cm -1 , with k0 being the photon wavevector), which are significantly larger than that of the SPPs on metal-based HMSs (k < 3k0) (12,13). In principle, the wavevectors predicted theoretically (Fig.…”

“…In such materials the SPPs exhibit a hyperbolic in-plane dispersion, i.e. the isofrequency surface in wavevector space describes open hyperboloids (2,6,(8)(9)(10)(11)(12)(13). Consequently, the polaritons on HMSs possess an extremely anisotropic in-plane propagation (i.e.…”

The Optical Properties and Plasmonics of Anisotropic 2D Materials

“…Because of their unique plasmon dispersion, the hyperbolic plasmons can propagate in a certain direction with a large density of states and higher filed confinement, leading to applications of spontaneous radiation enhancement, hyperlens, negative index materials, and thermal management . Many of these have been realized in hyperbolic metasurfaces, created by artificial subwavelength structuring from visible to microwave frequency ranges . However, in such artificially created hyperbolic surfaces, the wave vector of plasmon polaritons is limited by the inverse of the structure size, which hinders the potential of hyperbolic plasmons .…”

Active Anisotropic Coding Metasurface with Independent Real‐Time Reconfigurability for Dual Polarized Waves

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The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/admt.201900930.

Metasurfaces, planar arrays composed of subwavelength engineered phase-shifting scatters, have been an emerging platform for advanced and functional control of electromagnetic (EM) waves by manipulating the local properties of amplitude, phase, and polarization of the reflected or transmitted waves. [12][13][14][15][16][17][18][19] Nowadays, with the rapid development of modern wireless and optical technologies, increasing demands on high communication speed/quality, large data storage capacity are urgently required. [12][13][14][15][16][17][18][19] Nowadays, with the rapid development of modern wireless and optical technologies, increasing demands on high communication speed/quality, large data storage capacity are urgently required.

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