Design process of 3D metamaterial using spatial transforms
Introduction
Electromagnetic fields cannot be controlled inside a real, homogeneous material. However, these fields can be controlled by changing a local value of effective permeability and/or permittivity. It's may be done by use a some periodic structures (unit cell). Transformation optics (TO) [5–7] is one technique for designing periodic structures that are macroscopically inhomogeneous. The TO technique takes a spatial transform as the input, applies it to Maxwell's equations, pulls the transform out of the spatial coordinates and incorporates it into the constitutive parameters. Next step is generating the geometry of spatially variant lattices. This is a big challenging because the electromagnetic properties of the lattice depend on the size, direction and shape of the unit cells. Also often require adjacent unit cells to be the same, and shapes changing should be continuous, without distortion. This structure may be made (printed) by 3D printer.
