Spin-Enabled Plasmonic Metasurfaces for Manipulating Orbital Angular Momentum of Light

• Published in: Nano letters Vol. 13; no. 9; pp. 4148 - 4151
• Main Authors: Li, Guixin, Kang, Ming, Chen, Shumei, Zhang, Shuang, Pun, Edwin Yue-Bun, Cheah, K. W, Li, Jensen
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 11.09.2013
• Subjects: Angular momentum; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Degrees of freedom; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Mathematical analysis; Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals; Nanostructure; Orbitals; Physics; Plasmonics; Reciprocal space; Splitting; Structure of solids and liquids; crystallography; Surface and interface electron states; Metasurface; optical spin Hall effect; orbital rotation; spin−orbit interaction; Degrees of freedom; Reciprocal space; Electrical properties; Reciprocal lattice; Spin-orbit interactions; Plasmons; Momentum; Hall effect; Crystal structure
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/nl401734r

Here, we investigate the spin-induced manipulation of orbitals using metasurfaces constructed from geometric phase elements. By carrying the spin effects to the orbital angular momentum, we show experimentally the transverse angular splitting between the two spins in the reciprocal space with metasurface, as a direct observation of the optical spin Hall effect, and an associated global orbital rotation through the effective orientations of the geometric phase elements. Such spin–orbit interaction from a metasurface with a definite topological charge can be geometrically interpreted using the recently developed high order Poincaré sphere picture. These investigations may give rise to an extra degree of freedom in manipulating optical vortex beams and orbitals using “spin-enabled” metasurfaces.