title: Efficient coupling of propagating broadband terahertz radial beams to metal wires.
abstract: Bare metal wires have recently been demonstrated as waveguides for transporting terahertz (THz) radiation, where the guiding mode is radially polarized surface Sommerfeld waves. In this study, we demonstrate high-efficiency coupling of a broadband radially polarized THz pulsed beam, which is generated with a polarization-controlled beam by a segmented half-wave-plate mode converter, to bare copper wires. A total coupling efficiency up to 16.8% is observed, and at 0.3 THz, the maximum coupling efficiency is 66.3%. The results of mode-overlap calculation and numerical simulation support the experimental data well.
authors.affiliation: Centre for Quantum Technologies and Department of Physics, National University of Singapore, 3 Science Drive 2, 117543 Singapore.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Zheng
authors.forename: Natsuki
authors.initials: N
authors.lastname: Kanda
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Konishi
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuwata-Gonokami
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D003300:Copper / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008962:Models, Theoretical; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D012542:Scattering, Radiation; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D055053:Terahertz Radiation
chemical_list: D003300:Copper