设计了一种适用于光电子集成电路的表面等离子体波导结构.利用三维全矢量时域有限差分法对该波导结构进行了数值模拟, 并分析了其在基模传输时的模式场分布与金属结构顶角的关系以及其能量限制性.研究了该波导结构在不同金属材料下的有效折射率和传播长度对芯层宽度的依赖关系, 讨论了两个该波导结构之间的耦合长度、最大转移功率和彼此间的串扰.结果表明: 光场被高度限制在芯层区域, 在金属结构顶角为135°时, 其能量限制因子更高；在金属材料确定的情况下, 有效折射率随芯层宽度增大而减小, 而传播长度增大；在芯层宽度一定的条件下, 两个波导结构间的耦合长度随波导间距增大而增大, 最大转移功率和串扰随波导间距增大而减小.

A type of surface plasmonic waveguide applied in the optoelectronic integrated circuit was designed. It was simulated by using three dimensional full-vectorial finite-difference time-domain method. The dependence of distributions of electromagnetic field, effective index and propagation length of the fundamental mode supported by this waveguide on geometrical parameters were presented. The coupling length, maximum transfer power and crosstalk between two waveguide structures were studied. The simulation results showed: the light field is highly confined to the core layer area, and the energy restriction factor of light field is higher when the metal structure apex angle is 135 degrees; at a given metal, the effective index will decrease as the core width of ridge increases, meanwhile the propagation length of the fundamental mode will increase as radius of ridge increases; as the waveguide distance increases under given core width, the coupling length between two waveguide structures will increase and the maximum transfer power and crosstalk will decrease.