Millimeter Propagation and High Confinement in Rhombus-Based Hybrid Plasmonic Waveguides
HU Ru, LANG Pei-Lin, ZHAO Yu-Fang, DUAN Gao-Yan, WANG Lu-Lu, DAI Jin, CHEN Zhao, YU Li**, XIAO Jing-Hua
State Key Laboratory of Information Photonics and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876
Abstract:A hybrid plasmonic waveguide, consisting of two dielectric nanowires symmetrically put at the opposite corner angles of a rhombic metal, is proposed and numerically analyzed by the finite-element method. Simulations show that the present waveguide can achieve the millimeter propagation distance (1244 μm) and deep subwavelength mode area (5.5×10?3 μm2), simultaneously. Compared with the previous hybrid waveguides based on cylinder nanowires or flat films, the rhombic corner angles enable our waveguide to achieve both longer propagation distance and smaller mode area. This is due to the enhanced coupling between the dielectric guided mode in nanowires and the surface plasmon polariton mode at rhombic surface. Furthermore, the extreme confinement near the rhombic corner angles can strengthen the light-matter interaction greatly and make the present waveguide useful in many applications, such as nonlinear photonics, high-quality nanolasers and nanophotonic waveguides.