When a small metallic nanoparticle.is irradiated by incident light, the oscillating electric field can cause the conduction electrons to oscillate coherently, which excites the local surface plasmons （LSPs）. As is w...When a small metallic nanoparticle.is irradiated by incident light, the oscillating electric field can cause the conduction electrons to oscillate coherently, which excites the local surface plasmons （LSPs）. As is well known, excited LSPs can gather the energy of incident light to the surface of metallic nanoparticle. Recently, some nonspherical particles, e.g. tetrahedron, are suggested to obtain stronger localized electric field. We employ the discrete dipole approximation method to calculate the optical response of the tetrahedron nanoparticle, including the extinction and distribution of the electric field around the particle. The influences of some parameters, including the nanoparticle size, incident direction and polarization, are investigated to analyse the response modes and to obtain stronger localized electric field.展开更多
Sub-diffraction-limit imaging in the optical hyperlens based on cylindrical metamaterials is studied. Some parameters of hyperlens, such as the dispersive relation and the divergence angle of imaging, are numerically ...Sub-diffraction-limit imaging in the optical hyperlens based on cylindrical metamaterials is studied. Some parameters of hyperlens, such as the dispersive relation and the divergence angle of imaging, are numerically analysed with the ray trajectory method and effective medium theory. The dependence of imaging properties on dielectric constant is discussed. As a result, a 0° divergence angle is obtained for the best imaging effect. This work will be helpful for the design, structure fabrication and resolution improvement of the optical hyperlens.展开更多
Light propagation through a metal/nonlinear dielectric material/metal（M-NL-M） structure is numerically studied.The design parameters of the M-NL-M structure are found with the waveguide theory so that the structure ...Light propagation through a metal/nonlinear dielectric material/metal（M-NL-M） structure is numerically studied.The design parameters of the M-NL-M structure are found with the waveguide theory so that the structure only supports the symmetric surface plasmon polaritons（SPP（0）） mode and the antisymmetric surface plasmon polaritons（SPP（1）） mode.The coupling between the two modes within the M-NL-M structure is exploited.Through controlling the propagation constants of the two modes with the intensity-dependent dielectric constant of the nonlinear Kerr material,an effective all-optical control of plasmonic signal modulator can be realized with this M-NL-M structure.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 10474093 and the National Basic Research Programme of China under Grant No 2006CB302900.
文摘When a small metallic nanoparticle.is irradiated by incident light, the oscillating electric field can cause the conduction electrons to oscillate coherently, which excites the local surface plasmons （LSPs）. As is well known, excited LSPs can gather the energy of incident light to the surface of metallic nanoparticle. Recently, some nonspherical particles, e.g. tetrahedron, are suggested to obtain stronger localized electric field. We employ the discrete dipole approximation method to calculate the optical response of the tetrahedron nanoparticle, including the extinction and distribution of the electric field around the particle. The influences of some parameters, including the nanoparticle size, incident direction and polarization, are investigated to analyse the response modes and to obtain stronger localized electric field.
基金Supported by the National Basic Research Programme of China under Grant No 2006cb302905, Key Project of the National Natural Science Foundation of China under Grant No 60736037, Science and Technological Fund of Anhui Province for Outstanding Youth （08040106805）.
文摘Sub-diffraction-limit imaging in the optical hyperlens based on cylindrical metamaterials is studied. Some parameters of hyperlens, such as the dispersive relation and the divergence angle of imaging, are numerically analysed with the ray trajectory method and effective medium theory. The dependence of imaging properties on dielectric constant is discussed. As a result, a 0° divergence angle is obtained for the best imaging effect. This work will be helpful for the design, structure fabrication and resolution improvement of the optical hyperlens.
基金supported by the National Key Basic Research Program of China(No.2006CB302905)the Key Program of National Natural Science Foundation of China(No.60736037)+1 种基金the National Natural Science Foundation of China(Nos.10704070 and 60977019)the Science and Technological Fund of Anhui Province for Outstanding Youth(No.08040106805).
文摘Light propagation through a metal/nonlinear dielectric material/metal（M-NL-M） structure is numerically studied.The design parameters of the M-NL-M structure are found with the waveguide theory so that the structure only supports the symmetric surface plasmon polaritons（SPP（0）） mode and the antisymmetric surface plasmon polaritons（SPP（1）） mode.The coupling between the two modes within the M-NL-M structure is exploited.Through controlling the propagation constants of the two modes with the intensity-dependent dielectric constant of the nonlinear Kerr material,an effective all-optical control of plasmonic signal modulator can be realized with this M-NL-M structure.
