Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
SYSU-CMU Joint Institute of Engineering, SYSU-CMU International Joint Research Institute, Guangdong, China.
Sci Rep. 2017 Mar 21;7:45108. doi: 10.1038/srep45108.
Metamaterials have attracted more and more research attentions recently. Metamaterials for electromagnetic applications consist of sub-wavelength structures designed to exhibit particular responses to an incident EM (electromagnetic) wave. Traditional EM (electromagnetic) metamaterial is constructed from thick and rigid structures, with the form-factor suitable for applications only in higher frequencies (above GHz) in microwave band. In this paper, we developed a thin and flexible metamaterial structure with small-scale unit cell that gives EM metamaterials far greater flexibility in numerous applications. By incorporating ferrite materials, the thickness and size of the unit cell of metamaterials have been effectively scaled down. The design, mechanism and development of flexible ferrite loaded metamaterials for microwave applications is described, with simulation as well as measurements. Experiments show that the ferrite film with permeability of 10 could reduce the resonant frequency. The thickness of the final metamaterials is only 0.3mm. This type of ferrite loaded metamaterials offers opportunities for various sub-GHz microwave applications, such as cloaks, absorbers, and frequency selective surfaces.
超材料最近吸引了越来越多的研究关注。用于电磁应用的超材料由亚波长结构组成，旨在对入射的电磁（EM）波表现出特定的响应。传统的电磁（EM）超材料由厚而硬的结构构成，其形式因数仅适用于微波频段的较高频率（高于 GHz）。在本文中，我们开发了一种具有小尺寸单元的薄而灵活的超材料结构，为电磁超材料在许多应用中提供了更大的灵活性。通过结合铁氧体材料，超材料的单元的厚度和尺寸可以有效地缩小。描述了用于微波应用的柔性铁氧体加载超材料的设计、机理和开发，包括模拟和测量。实验表明，磁导率为 10 的铁氧体薄膜可以降低谐振频率。最终超材料的厚度仅为 0.3mm。这种铁氧体加载超材料为各种亚 GHz 微波应用提供了机会，例如斗篷、吸收体和频率选择表面。
