Park Junghyun, Kim Kyoung-Youm, Lee Il-Min, Na Hyunmin, Lee Seung-Yeol, Lee Byoungho
National Creative Research Center for Active Plasmonics Application Systems, Inter-University Semiconductor Research Center and School of Electrical Engineering, Seoul National University, Seoul, Korea.
Opt Express. 2010 Jan 18;18(2):598-623. doi: 10.1364/OE.18.000598.
We present comprehensive case studies on trapping of light in plasmonic waveguides, including the metal-insulator-metal (MIM) and insulator-metal-insulator (IMI) waveguides. Due to the geometrical symmetry, the guided modes are classified into the anti-symmetric and symmetric modes. For the lossless case, where the relative electric permittivity of metal (epsilon(m)) and dielectric (epsilon(d)) are purely real, we define rho as rho = -epsilon(m)/epsilon(d). It is shown that trapping of light occurs in the following cases: the anti-symmetric mode in the MIM waveguide with 1 < rho < 1.28, the symmetric mode in the MIM waveguide with rho <<1, and the symmetric mode in the IMI waveguide with rho <1 . The physical interpretation reveals that these conditions are closely connected with the field distributions in the core and the cladding. Various mode properties such as the number of supported modes and the core width for the mode cut off are also presented.
我们展示了关于等离子体波导中光捕获的综合案例研究，包括金属 - 绝缘体 - 金属（MIM）和绝缘体 - 金属 - 绝缘体（IMI）波导。由于几何对称性，导模被分为反对称模和对称模。对于无损情况，其中金属（ε(m)）和电介质（ε(d)）的相对电容率为纯实数，我们将ρ定义为ρ = -ε(m)/ε(d)。结果表明，在以下情况下会发生光捕获：MIM波导中1 < ρ < 1.28时的反对称模，ρ <<1时MIM波导中的对称模，以及ρ <1时IMI波导中的对称模。物理解释表明，这些条件与纤芯和包层中的场分布密切相关。还给出了各种模式特性，如支持模式的数量和模式截止的纤芯宽度。
