Flexible 2.5D Metamaterial with High Mechanical Bearing Capacity for Electromagnetic Interference Filters at Microwave Frequency

Abstract

Herein, the conception of 2.5D metamaterial is proposed. The basic idea of the 2.5D metamaterial is to build “3D” metamaterial by stacking 2D metasurfaces layer‐by‐layer. In this design, the trapezoidal prism units (3D) is built up by stacking a series of rectangle units (2D) together. This means, in the conception of 2.5D metamaterial, any kind of 3D structure with complex geometrical shape can be easily built up by controlling the 2D shape in each layer, which provide a new way for the fabrication of 3D complex units. Furthermore, paper is chosen as the substrate of 2D layer, because the interconnected lignocellulosic microfibers in paper will not only bring in flexibility to the 2.5D metamaterial but also strong mechanical strength. The results show that the 2.5D metamaterial still maintain a good filtering performance at 11 GHz when the pressure loading rise up to 7 MPa, whereas the classic 3D metamaterial (built by copper‐clad plate) undergoes a fracture failure. The conception and demonstration of 2.5D metamaterial with high mechanical property not only overcome the lacking of the basic structural carrying capacity in 3D electromagnetic metamaterial but also give new idea to the design of multifunctional metamaterial.