Controlling and manipulating light is one of the greatest challenges of current and future technologies. The HelicalMETA project addresses this issue by taking advantage of two major recent breakthroughs in the field of photonics: metamaterials and topological protection. Metamaterials, artificial structures composed of building blocks smaller than the wavelength of the involved radiation, offer unprecedented control over electromagnetic radiation. Their electromagnetic response, which depends on appropriate design, can surpass optical effects found in nature, and enable exotic phenomena and effects such as negative refraction or perfect lensing. On the other hand, topology, a branch of mathematics that studies the properties of shapes under continuous transformations, has recently emerged as a novel route to engineer the flow of light. Using insights from topology, researchers have developed photonic platforms that are insulating in the bulk but allow light to flow along their edges or surfaces without scattering, even around corners and imperfections.
The aim of this project is the demonstration of several key functionalities for the control and manipulation of light, including subwavelength imaging, sensing, and topological properties, provided by a helical-shaped wire metamaterial formed by an array of parallel metallic spirals (see image). Findings will enable the development of novel imaging devices, and may also have applications in magnetic resonance imaging, sensing, and scattering-immune waveguiding.
The HelicalMETA research project is an internal IT project involving the Antennas and Propagation Groups from Coimbra (Tiago A. Morgado, David E. Fernandes and Sylvain Lannebère) and Lisboa (Paloma A. Huidobro and Filipa R. Prudêncio).