Metamaterials are carefully engineered materials that possess desirable properties and can be used to manipulate electromagnetic, acoustic, or other types of waves in interesting ways. Some materials scientists and engineers have been trying to use these materials to develop so-called invisible devices, or, in other words, devices that do not disturb the environment around them or reveal their presence to other technologies nearby.

Most proposed approaches for realizing invisible devices entail surrounding devices with a metamaterial shell that prevents scattering. While devices created using these strategies do not disturb their surrounding environment, they still distort what is happening within the metamaterial shell, thus they remain partly visible.

Researchers at Fudan University have introduced a new approach to realize devices that are truly and entirely invisible using metamaterials. Their proposed solution, outlined in a paper published in Physical Review Letters, was found to eliminate scattering effects both outside and inside a metamaterial cloaking shell.