Diverse surface waves supported by bianisotropic metasurfaces

TL;DR

This paper demonstrates that a single-layer bianisotropic metasurface with specific symmetries can support a wide variety of surface waves with different polarization states, opening new avenues for surface wave applications.

Contribution

It reveals that a metasurface with D2d symmetry can support diverse surface wave polarizations, including TE, TM, longitudinal, and elliptically polarized modes, which was not previously shown.

Findings

Supports both TE and TM surface waves along principal directions

Supports longitudinal and elliptically polarized TEM modes along diagonals

Potential for novel surface wave phenomena and device applications

Abstract

Surface waves supported by structured metallic surfaces, i.e. metasurfaces, have drawn wide attention recently. They are promising for various applications ranging from integrated photonic circuits to imaging and bio-sensing in various frequency regimes. In this work, we show that surface states with diverse polarization configurations can be supported by a metasurface consisting of a single layer of bianisotropic metamaterial elements. The structure possesses D2d symmetry, which includes mirror symmetry in the xz and yz plane, and C2 rotational symmetry along y = +-x axis. Due to this unique symmetry, the metasuface supports both transverse electric (TE) and transverse magnetic (TM) waves along kx and ky directions, while a purely longitudinal mode and an elliptically polarized transverse electromagnetic (TEM) mode along ky = +-kx directions. The versatility of the surface modes on the metasurface may lead to new surface wave phenomena and device applications.