Plasmonic metasurface superscatters driven by infrared surface lattice resonances

Abstract

We have demonstrated that plasmonic metasurfaces composed of arrays of Au bowtie nanoantennas can support an infrared bidirectional superscattering state. This state arises when the nanoantennas are coherently coupled together, forming a surface lattice resonance that efficiently guides the infrared range (1–1.6 μm) of incident broadband white light along the plane of the arrays. This process exhibits strong polarization dependence, offering an “OFF” state where a 90° rotation of the incident light polarization effectively suppresses in-plane scattering from all sides. Stokes parameters analysis is used to study the states of polarization of the scattering, demonstrating transformation into a complete depolarized state. The results emphasize the significant influence of the multipolar modes of these nanoantennas on the interference processes associated with such scattering phenomena, and their potential applications in polarization optical switching and unique beamsplitting.