Metamaterials: a new technology for the 21st century

Coinciding with the start of the new millennium, a new subject has sprung up in the field of science and technology: what are known as metamaterials. These are artificial structures, based on periodic groupings of conventional materials (metals and/or dielectrics), through which unusual electromagnetic, optical and even acoustic properties can be achieved. This is why it is necessary to structure and design suitably the inclusions formed by these media, as through them it is possible to obtain characteristics that go beyond those presented by their constitutive elements. Among these, we can highlight the propagation of backward waves, negative refraction, super-resolution and light-guiding. Metamaterials can be applied in very diverse fields, such as optics, electronics, medical diagnosis and telecommunications. Since the big bang of metamaterials in the year 2000, research activity on the subject has grown exponentially, at the same time as its media and social impact has increased (mostly deriving from news items published about invisibility), while industry has also shown interest in the area.