Focusing of cross-polarized light by plasmonic nanoantenna metasurfaces with phase discontinuities

摘要

An ultrathin metasurface which is constructed with planar arrays of V-shaped nanoantennas is presented to realize the focusing of cross-polarized light. Based on the particular resonance properties of the V-shaped antennas, we can design the amplitude, phase, and polarization state of the scattered light, and then choose the proper antennas to satisfy the optical phase discontinuities calculated from the equal optical length principle. Numerical simulation of an illustrative metasurface is performed through finite element method (FEM) and shows agreement with the pre-design. In addition, broadband light focusing is also discussed in this article. This lens may find potential applications in integrate optics, controllable focusing, wave plates, and optical interconnection devices.