Lv Jingwei, Zhang Xiaoming, Yu Xuntao, Mu Haiwei, Liu Qiang, Liu Chao, Sun Tao, Chu Paul K
School of Physics and Electronic Engineering, Northeast Petroleum University, Daqing 163318, China.
College of Physics Science and Engineering Technology, Yichun University, Yichun 336000, China.
Nanomaterials (Basel). 2020 Jul 23;10(8):1440. doi: 10.3390/nano10081440.
An optical nanoantenna consisting of a Au-dielectric core-shell nanocube dimer with switchable directionality was designed and described. Our theoretical model and numerical simulation showed that switching between forward and backward directions can be achieved with balanced gain and loss, using a single element by changing the coefficient in the core, which can be defined by the relative phase of the polarizability. The optical response indicated a remarkable dependence on the coefficient in the core as well as frequency. The location of the electric field enhancement was specified by the different coefficient and, furthermore, the chained optical nanoantenna and coupled electric dipole emitted to the optical nanoantenna played significant roles in unidirectional scattering. This simple method to calculate the feasibility of unidirectional and switchable scattering provides an effective strategy to explore the functionalities of nanophotonic devices.
设计并描述了一种由具有可切换方向性的金-电介质核壳纳米立方体二聚体组成的光学纳米天线。我们的理论模型和数值模拟表明，通过改变核中的系数，利用单个元件可以在正向和反向之间实现切换，且增益和损耗平衡，该系数可由极化率的相对相位定义。光学响应表明对核中的系数以及频率有显著依赖性。电场增强的位置由不同的系数确定，此外，链式光学纳米天线以及耦合电偶极向光学纳米天线的发射在单向散射中起重要作用。这种计算单向和可切换散射可行性的简单方法为探索纳米光子器件的功能提供了一种有效策略。
