Department of Applied Physics, School of Science and Shenzhen Research and Development Institute, Northwestern Polytechnical University, Xi'an, 710129, China.
Ames Laboratory-U.S. DOE and Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA.
Adv Mater. 2019 Sep;31(39):e1903206. doi: 10.1002/adma.201903206. Epub 2019 Aug 5.
Artificially structured metamaterials with metallic or dielectric inclusions are extensively studied for exotic light manipulations via controlling the local-resonant modes in the microstructures. The coupling between these resonant modes has drawn growing interest in recent years due to the advanced functional metamaterial making the microstructures more and more complex. Here, the suppression of magnetic resonance of a dielectric cuboid, an analogue to the scattering cancellation effect or radiation control system, realized with an exterior cloaking in a hybrid metamaterial system, is demonstrated. Furthermore, the significant modulation of the absorption of the dielectric resonator in the hybrid metamaterial is also demonstrated. The physical insight of the experimental results is well illuminated with a classical double-harmonic-oscillator model, from which it is revealed that the complex coupling, i.e., the phase of coupling coefficient, plays a crucial role in the overall response of the metal-dielectric hybrid system. The proposed design strategy is anticipated to form a more straightforward and efficient paradigm for practical applications based on radiation control via versatile mode couplings.
人工结构的超材料，具有金属或介电的内含物，通过控制微结构中的局域共振模式，广泛应用于奇异的光操控。由于先进的功能超材料使微结构变得越来越复杂，这些共振模式之间的耦合近年来引起了越来越多的关注。在这里，通过在混合超材料系统中使用外部覆盖物，实现了对介电长方体的磁共振的抑制，这类似于散射消除效应或辐射控制系统。此外，还展示了在混合超材料中介电谐振器的吸收的显著调制。实验结果的物理见解很好地用经典的双谐波振荡器模型来解释，从该模型中揭示出，复杂的耦合，即耦合系数的相位，在金属-介电混合系统的整体响应中起着关键作用。所提出的设计策略预计将为基于通过多功能模式耦合进行辐射控制的实际应用形成一种更直接、更有效的范例。
