Hybrid design and prototyping of metamaterials and metasurfaces

Abstract

Metamaterials are engineered materials conceived and designed to achieve very special or even unique physical properties, which depend on the designed micro or nanostructures, more than on the chemical composition of the raw materials employed for their fabrication. Normally metamaterials are made of periodic repetitions of unit cells or Boolean combinations of lattices or porous building blocks. Metasurfaces are the quasi-two-dimensional version of metamaterials and are generally applied to controlling electromagnetic and acoustic waves reaching them. Metamaterials are mainly created through high-precision additive manufacturing technologies, while metasurfaces are normally obtained using micromanufacturing techniques from the electronics industry and laser patterning methods. Consequently, the potential benefits and industrial applications of multi-scale or hierarchical metastructures, which could be obtained by merging metamaterials and metasurfaces, remain unexplored. Through the innovative combination of 3D CAD modelling resources and specific tools for computational mapping of topographical 2D images this study validates the possibility of texturing the building blocks and unit cells of metamaterials, hence reaching designs with interwoven metamaterials and metasurfaces. These microtextured lattices are additively manufactured, using two-photon polymerisation, to demonstrate the feasibility of bridging the gap between metamaterials and metasurfaces and analyse current challenges and potential applications of these digital materials.

Keywords

• digital materials
• metamaterials
• metasurfaces
• rapid prototyping
• additive manufacturing
• two-photon polymerisation