提出了一种新型表面等离激元波导系统, 并对其模式特性和对纳米微粒产生的光学力进行了研究。采用有限元软件(COMSOL)对该系统进行了数值模拟和理论分析, 发现在该结构纳米级的间隙中可以形成深亚波长电磁能量的束缚。由于双波导结构之间强烈的耦合作用, 相比于已有的一些表面等离激元波导, 光学力至少提高了一个数量级, 达到了4200fN/W以上, 同时被捕获粒子的局域范围仅有几十纳米。该波导系统可以用于强力、高精度纳米级光镊的设计和研究。

In this paper, a new type of surface plasmon waveguide system was proposed and its mode characteristics and the optical force exerted on the nano particles were studied. By the calculation of numerical simulation and theoretical analysis of the system through the finite element software (COMSOL), it is found that a deep sub wavelength energy bound can be formed in the gaps of the nanoscale structure. Due to the strong coupling effect between the two waveguide structures, the optical force increases at least one order of magnitude compared with some existing surface plasmon waveguides and reaches over 4200fN/W. The local scope of the captured particles is only a few dozens of nanometers. The waveguide system proposed in this paper can be used for the design and research of powerful and high-precision nanoscale optical tweezers.