The Research On The Excitation, Losses And Interconnect Of The Silver Nanowire Waveguides

The optical interconnects are the potential choice to overcome the difficulties of electronic interconnects, such as time delay, power dissipation and bandwidth limitation. Taking advantage of the ability of both photonic and electronic devices, the system based on OEIC (Optoelectronic integrated circuit) chip will possess tremendously-enhanced information processing ability. Silver nanowire is a candidate for the optical interconnect due to its ability to support surface plasmon polariton. The optical properties of the chemically-synthesized silver nanowire are invesitigated experimentally in this thesis. Illuminated and imaged in a far-field microscope, several kinds of the excitation scheme of SPP(surface plasmon polaritons) are realized experimentally; the propagation losses and bending losses of the silver nanowires are measured and analyzed. Also, some functional devices composed with silver nanowires and ZnO optical waveguides are fabricated and measured. The main works and conclusions are as follows:Silver nanowire waveguide was bent and the bending curvature was controlled with a fiber probe. Taking away the propagation loss by the ratio of the emission intensity of the bending and the straight silver nanowire, the bending loss of the silver nanowire putting on the glass substrate was investigated at different bending radius, wire diameters and exciting wavelengths. Two kinds of silver nanowires with diameters of 200nm and 270nm are measured at excitation wavelengths of 632.8nm and 780nm. The experiments indicate that bending loss increases as the bending radius decreases or the wire diameter increases. Our results can be used to optimize the fabrication of bending waveguide in OEIC.A silver nanowire with diameter of 200nm was put on the glass substrate, its propagation loss was accurately measured in the branched-routing structure since the propagating length of SPP can be varied without changing the excitation condition. The propagation loss was measured as 115μm^-1 with excitation wavelength of 632.8nm andμm ^-1 with excitation wavelength of 780nm, which indicates that the propagation loss of SPP is smaller at longer-wavelength excition. 0.0.0923 Several coupling devices based on silver nanowire waveguide were realized and investigated experimentally, including 2×2 beam splitter based silver nanowire, S-shaped silver nanowire waveguide, coupled beam splitter based on silver nanowire and ZnO waveguide. The splitting ratio of the 2×2 beam splitter can be altered as you want by changing the coupling length, and here SPP splitting ratio—0:1, 1:0 and 3:2 have been realized experimentally. The S-shaped nanowire waveguide can be used to connect two seperated straight waveguides, the transmittance of the S-shaped nanowire dosen't depend on the end-to-end distance of the S-shape but on the arc length and curvature radius of the S-shaped nanowire. The silver nanowire was also used as a coupler between two paralleled ZnO waveguide. Our experimental exploration will contributed to the capatability of nano OEIC and the trandional opical waveguides.Four schemes of SPP excitation along silver nanowires are explored: the end of the nanowire, particle-nanowire coupling system, bending corner of the nanowire and the cross of two silver nanowires. Our experiments indicate that SPP can be excited by far-field illumination if the symmetry of the silver nanowire was broken. In the end excitation scheme, we found a consine dependence of the excitation efficiency on the polarization of the incident light, the initial pahse of the consine dependence was related to the topography of the end face and the wavelength of the light.